Science topic

Efficiency Analysis - Science topic

Explore the latest questions and answers in Efficiency Analysis, and find Efficiency Analysis experts.
Questions related to Efficiency Analysis
  • asked a question related to Efficiency Analysis
Question
1 answer
Hello to everyone!
I am doing a research on bank branches efficiency, and I want firstly to count Malmquist efficiency index (I have data for 3-year period), and then run a double bootstrapped truncated regression, with Malmquist Index as dependent variables and one exogenous variable.na
Maybe someone can advice me, how can I run such a regression on Malmquist index in R?
Thank you very much in advance!
Best regards,
An
Relevant answer
Answer
Take a look at this search for some useful information. Best wishes David Booth
  • asked a question related to Efficiency Analysis
Question
6 answers
Hello Everyone,
I want help to evaluation efficiency of DC-DC power converter with Matlab/Simulink. Is there any block for the calculation? Please share any ideas regarding this.
Thanks
Relevant answer
Answer
In general, the efficiency of a power converter (AC-DC or DC-DC) is assessed by comparing its input power to its output power. To be more specific, the converter's efficiency is determined by dividing its output power (Pout) by its input power (Pin).
For MATLAB, these tutorials might help:
  • asked a question related to Efficiency Analysis
Question
3 answers
I know that R Software specifically Benchmarking package can be used to assess the MEA scores but I don't know how to capture the non-discretionary inputs when running a non-oriented analysis.
Relevant answer
Sincere enquiry: Isn't it that DEA a non-parametric method for analysing efficiency? Debora Addo 's questions seems to be looking for a software as opposed to a technique? Thank you -:
  • asked a question related to Efficiency Analysis
Question
3 answers
I know that using non-discretionary input could be an issue in the original, input-oriented DEA models where input can be expanded and/or contracted. The concern, I think, was that we don't want to produce efficiency scores suggesting efficiency could be improved by reducing uncontrollable (non-discretionary) inputs. However, I wonder if the inclusion of non-discretionary input is as consequential for output-oriented VRS DEA models? Most of the literature is based on input-oriented DEAs. Any comments will be appreciated, Thanks.
Relevant answer
Answer
good question
  • asked a question related to Efficiency Analysis
Question
3 answers
I want to conduct a study to check the impact or shock of predicted estimates of technical efficiency of the farmers for agricultural production on the ecological footprint and Emissions of Green House Gases for a time series panel data.
Relevant answer
Answer
The use of aquatic weed (Eichornia crassipes) as a sustainable approach to convert waste to wealth through suitable techniques"
  • asked a question related to Efficiency Analysis
Question
4 answers
I want to purify my insoluble organic compound from sodium chloride through washing.
I have done my first trial with distilled water having tds approx 44 p.p.m and the second with fresh ground water having tds approx 500 p.p.m.
The results differs in both trials.
So how t.d.s and hard minerals affects the solubility of sodium chloride in water?
how can i calculate the ratio of solubility based on water quality (t.d.s).
Suggestions are highly appreciated.
Relevant answer
Answer
Each water has a capacity to dissolve any solute. After reaching such level, the water is saturated. Thus, it is not surprizing to see high TDS water has lower capacity to dissolve NaCl, compared low TDS one
  • asked a question related to Efficiency Analysis
Question
5 answers
Dear Colleague,
Part of my Ph.D. thesis needs to be completed questionnaire, which, unfortunately, due to Covid 19, we cannot attend the company under review. For this reason, I request supply chain experts who wish to complete the questionnaire to notify me, that I will email the questionnaire to them. It would be your generosity to respond to the questionnaires and also distribute them among your colleagues, students, and networks.
Thank you in advance for your help and cooperation.
Relevant answer
Answer
  • asked a question related to Efficiency Analysis
Question
6 answers
I want to compare the efficiencies of different machine learning techniques for Structural reliability and surrogate modelling. Although my problem is specific, I think there should be well-known criteria for that. Unfortunately, I have not found any in the literature!
One simple idea is to multiply accuracy by the number of calls or time, but it is really not a very proper criterion most of the time.
How can we define good criteria? is it a good idea to go with a weighted multiplication based on a specific objective? or is there any well-known method for making this comparison?
I appreciate your help with this challenge!
Relevant answer
Answer
Your very welcome Sajad Saraygord Afshari
Kind Regards
  • asked a question related to Efficiency Analysis
Question
15 answers
I have to isolate and then properly purify some of azo pigment compounds.
i have done TLC and column chromatography of these pigments but ending up with the seperation of thier isomers only.
i believe that my pigment compounds still have some side products and impurities that i am unable to separate out.
suggestions required for highly efficient isolation and purification of the following pigment compounds attached.
Relevant answer
Answer
As Jack stated, your Rf value are to high to expect a separation. You will have to adjust the polarity of your mobile phase
  • asked a question related to Efficiency Analysis
Question
2 answers
Dear Colleagues,
May I know how to calculate the Energy Efficiency analysis of AODV routing protocol in MANET, with the formula? If available any good reference will be fine.
Thank you in advance.
Relevant answer
Answer
  • asked a question related to Efficiency Analysis
Question
8 answers
Dear all.
I would like to ask you some sort of guideline, developed from your own experience or from references, about condition where it is better to use the "traditional" DEA and when is more appropriate to consider for the Slack Based alternative, (Tone, 2001 and Tone, 2002). I mentioned conditions having in mind for istance sample sizes, area of investigation (healthcare, transportation ecc.) or other instrument combined with the DEA analysis (regressions, bootstrap, bayesian methods...).
I thank you in advance.
Stefano
Relevant answer
Answer
Stefano Martinazzi when we use radial measure, the DMU reach the efficient frontier but if it has any slack left, it will be weakly efficient (there may be more chances to reduce the inputs or outputs). However, when we use slack based measure, the inefficient firm become the strongly efficient firm once it reaches the efficient frontier
  • asked a question related to Efficiency Analysis
Question
2 answers
I am interested in obtaining the efficiency scores of the public education system across the country's municipalities. I have 60 municipalities with various inputs and outputs over a period of 5 years. I am able to obtain the efficiency scores of them on a yearly basis - 300, but I am interested in obtaining the overall efficiency score of each municipality over the years, what is the simplest method to complete this task (Preferably in r software)? Thank you!
Relevant answer
Answer
You can use the Malmquist TFP index which can be constructed from the effiency scores of each year.
If you know how to get by R the efficiency scors (by using for example the Benchmarking package) then you use the definiton of the Malmquist index and you will be able to say by how much the productivity has increased among years. And you can get the technichal and efficiency changes.
  • asked a question related to Efficiency Analysis
Question
4 answers
The algorithmic management of today comes in the form of AI-based solutions but it still is an algorithm with a binary system intact. What do you think of its usage and its novelty? How can we use AI-based evaluation to measure the efficiency of someone's work?
Relevant answer
Answer
Hi @Valeria Demchenko
This is an interesting discussion !
I believe that artificial intelligence can make Taylor's vision more efficient in many ways and with new methods.
What do you think about the fuzzy attitude and rules of the Taylor Theory?
I suggest you think about this.
Good luck
  • asked a question related to Efficiency Analysis
Question
5 answers
I am trying to assess or predict the use of one specific technology that might have several impacts on an operational activity - drilling in the oil industry. This technology is supposed to improve the efficiency of drilling in various aspects among which the economic aspects are of high importance to me.
I am seeking a quantitative method that can help me measure and predict the economic outcomes of this change. So I would be thankful if anyone could suggest using any method for this need.
Relevant answer
Answer
You may want to incorporation of both qualitative and quantitative risk parameters. The applicability of various probability distributions to the (e.g petroleum project development cost analysis).
Each of the risk analysis technique has its own advantages and shortcomings. The quantitative analysis techniques such as Fault Tree Analysis and Event Tree analysis can yield definitive results but usually require enormous effort in model development, data collection and quantification of uncertainties. The qualitative (or semi-quantitative) risk analysis tools such as PHA or FMEA yield quick results that are not quantitative, but can be cost-effectively used to prioritize the relative risks (in relation to other risks present or posed by the product/system).
  • asked a question related to Efficiency Analysis
Question
2 answers
I am planning to conduct a meta-analysis on the efficiency of MFIs from existing literature, restricted to DEA/ SFA based studies. However, most DEA/ SFA based meta-analyses (Thiam and Bravo-Ureta (2005); Odeck and Bråthen (2012); Kiadaliri et. al (2013) Fall et. al (2018)) use the mean technical efficiency (MTE) as a measure of effect size usually without compensating for sampling bias (they included sample size as a moderating variable instead). Is there any other way to compute a different measure of effect size for DEA/ SFA based studies that compensates for bias like the Hedge's g or Fisher's z?
Relevant answer
Answer
Anirban,
You are into something interesting yet, intricate. I agree with Ahmed that we need to know what your goal is with the analysis/ research. The intricacy of your problem since you are dealing with Meta-analysis of technical efficiency (TE) studies, is that you need to know how representative those individual studies were in terms of representing all the DMU’s in the sectors they addressed. Good scientific papers will always address the representativity of their data sets and, they are normally representative such that Mean TE’s (MTE) can be considered as representative. This is the reason that Thiam and Bravo-Ureta (2005); Odeck and Bråthen (2012); Kiadaliri et. al (2013) Fall et. al (2018)) use the mean technical efficiency (MTE) as a measure of effect size without further consideration of sampling bias. Therefore, and in the first instance, you could proceed by using the reported MTE’s as well.
Next and given that you want to consider sampling bias as something new which has not been considered in the literature of meta-analyses of MTE’s, the only option left for you is to go through the abundant literature and ask the individual authors how representative their data were with regards to the total population of their DMUs. If their studies were not all that representative, you may use the information they provide to correct for sampling bias and then produce a paper that goes further to pinpoint the sampling issue. This may be a cumbersome process that may take time to accomplish since a meta-analysis normally includes many studies.
Finally, if you feel that the TE data should be normally distributed and you have good arguments for it, you could apply e.g., the Fisher transformation; but please explain why. Note now that SFA-based-TE’s for instance, apply non-normal distributions built on real observations!
I hope this helped.
  • asked a question related to Efficiency Analysis
Question
9 answers
I am doing frontier analysis of banks and I calculated the robust efficiency scores for each of the bank. Now I want to run a bootstrap truncated regression with efficiency scores as dependent variable to examine their relationship with characteristics of banks. How can I run the method proposed by simar and wilson (20007) in R. Please help in this regards.
Relevant answer
Answer
A Latif Patwary You can use the "lt" function from this package https://cran.r-project.org/web/packages/truncSP/truncSP.pdf if you want to only use truncated bootstrapped regression.
However, if you want to execute simar and Wilson(2007,2011) two step bootstrapping algorithm with environment variables then use "dea.env.robust" from from https://cran.r-project.org/web/packages/rDEA/rDEA.pdf.
if you want to run a simple truncated regression then use "truncreg" function from https://cran.r-project.org/web/packages/truncreg/truncreg.pdf
Hope this will help you. All the best.
  • asked a question related to Efficiency Analysis
Question
3 answers
Suppose, in case of input-oriented approach, for one firm has the CRS efficiency is 0.8682 and the VRS efficiency score is 0.96652. What we can say by both of these two results?
Scale efficiency = 0.8982. What we can understand from this?
Relevant answer
Answer
In general, for CRS and VRS "how far the value from unit value (1.000)".... closer to 1.000 the high the firm efficiency...
  • asked a question related to Efficiency Analysis
Question
9 answers
Hello, Everybody!
I wil be grateful for any help. I have a problem with frontier function. I want to make a model of life expectancy in 11 countries depending on some factors (consumption of alcohol, school years, gross national income per capita and etc.) using frontier method for panel data (from 2000 to 2013 year) to calculate efficiency of national care system at the end. I've made a model and then used the command
predict te, te
for each country but the meanings are very small and almost the same. Due to the fact I took into consideration different countries (from Australia to Nigeria) it is impossible that efficiency of national care system are equal. Besides, I've calculated u and tried to calculate e^(-u), but what is the difference between u and te? I've spent a lot of time to sort out this, but overall I don't understand clearly:(
Thanks! 
Relevant answer
Answer
The stochastic frontier model can be used
  • asked a question related to Efficiency Analysis
Question
5 answers
Is there any specific book/research paper where i can find a validated model of relation between Inverter temperature, Ambient Temerature and Inverter Efficiency? Reduction in Inverter's efficiency at any given temerature compared to STC condition due to internal heat generated in Inverter plus the Convective heat from ambient temperature.
I know that...
As the inverter works to convert DC power to AC power, it generates heat. This heat is added to the ambient temperature of the inverter enclosure, and the inverter dissipates the heat through fans and / or heat sinks.  The heat needs to stay below a certain level at which the materials in the inverter will start to degrade.  Insulation will become brittle, solder can expand and crack and metal components in capacitors can fatigue. 
In order to keep the heat low, the inverter will stop generating power or reduce the amount of power it generates by “derating” as it passes programmed temperature milestones.  Most inverters will derate at around 45 – 50 Degrees C.
But is there any specific relation formula or validated model or something?
Relevant answer
Answer
As the ambient temperature increases the switching transistors are the the elements which mostly suffer from the increasing the ambient temperature.
As the ambient temperatures increases the the rate of heat flow from the transistor to the ambient decreases. There is a derating factor of the allowed power dissipated in the device as the environmental temperature increases. This power derating curve is given in the data sheet of the power transistors.
As for the conversion efficiency it will not suffer much as the ambient temperatures is still in the allowed range. This is because the on resistance of the MOSFET transistors increases but the power dissipated in the transistor is still small compared to the load power.
One can consider that the loss deficiency is proportional to VL/VI= (Vi- Von)/Vi
where VL is the load voltage, Vi is the input voltage, Von is the on voltage of the MOS transistor switch. Von is the term that will increase with ambient temperature and so the efficiency will basically decrease. But this decrease is small if the transistor is operated within the allowed dissipated power.
A said before, you can derive an expression for the efficiency and quantify this problem. For the calculation of the loss efficiency please follow the paper in the link:
Best wishes
  • asked a question related to Efficiency Analysis
Question
7 answers
I would like to get information and articles about measurements of efficiency in zakat institutions.
Relevant answer
Answer
Efficiency and productivity performance of zakat funds in Algeria
  • asked a question related to Efficiency Analysis
Question
43 answers
Dear collegues, researchers and practicioners on DEA.
In the 16th International Conference on Data Envelopment Analysis we presented deaR, a new R package for DEA. Now, it is a pleasure for me to announce that deaR is available to be installed and used.
deaR has been designed and built so that non-R users can easily use it. This package allows to run a wide variety of models based on DEA:
  • Conventional DEA models: CCR, BCC, directional distance function multiplier, additive, non radial, sbm, radial super efficiency, additive super efficiency, sbm super efficiency, cross efficiency, bootstrapping, etc.
  • Malmquist index
  • Fuzzy DEA models: Kao and Liu´s model, some possibilistic DEA models, fuzzy cross efficiency.
You can get a brief introduction tutorial to install and use deaR (in English, Spanish, and Chinese) by clicking on the following link:
deaR is not only oriented to research but also teaching. For that reason, deaR provides some datasets that come from articles already published. These datasets are used in the deaR function examples to replicate the results of the articles.
We would really appreciate if you could spread the information about deaR among your colleagues and students.
We will release a deaR shiny version (an interactive web app) son. We will inform you when it is available.
Any comments and suggestions to improve deaR will be really appreciated. We also accept suggestions of DEA models to be considered for being programmed in new versions of deaR.
Best regards.
Relevant answer
Answer
How to cite deaR package:
Coll-Serrano, V.; Benítez, R. and Bolós, V. (2018). Data Envelopment Analysis with deaR. University of Valencia, Spain. R package version 1.2.0
  • asked a question related to Efficiency Analysis
Question
3 answers
Dear all,
I used those two types of regression to estimate effects of environment factors on hospital efficiency.
However, they gave me opposite results. For instance, in FR percentage of people above 65 was negatively associated with DEA score, whereas in DBTR it was positively associated. The same results was for turnover rate.
I appreciate if you could explain me such contradictory.
Relevant answer
Answer
  • asked a question related to Efficiency Analysis
Question
2 answers
I am performing a Stochastic Frontier Analysis on unbalanced panel data in R with the package frontier (based on Battese & Coelli 95). I wonder how can we check for autocorrelation / endogeneity. The residuals() function returns the residuals, which consist of both the noise term and the inefficiency term, i.e. residual = y - f(x) = v - u. I am not sure if one can use these residuals to test for heteroscedasticity (Breush-Pagan test) or autocorrelation (LM test). Have you seen this in the literature?
Relevant answer
Answer
For endogeneity issue, you can use the control function approach to estimate and test. For serial correlation, are you trying to check for v or u or both?In any case, it is much harder since you have unbalanced panel and individual v and u are not identified. I have not seen any work on testing for serial correlation in SFM. If you are worry about serial correlation my suggestion is to use complete dynamic modeling on the frontier.
  • asked a question related to Efficiency Analysis
Question
5 answers
I have simulated the 0.37KW capacitor start induction motor in ansys maxwell RM Xprt. Its efficiency is 45% (percent), results attached. These are no load results. I have few questions
How to perform the on- load analysis of motor using RM Xprt or 2D analysis?
How to optimize the winding design, wire size and no of turns etc.?
How to select the starting capacitor for this motor?
How to select the rotor shape, its dimensions and torque optimization?
How to increase the overall efficiency to fulfil the IE1 and IE2 standard?
Simulation results shows that stator losses are 129watt, thats hufe losses in 373 watt motor, How can I reduce it ?
How to select the switching time of auxilery winding ?
Any paper, books, tutorials or presentation or videos that can help me in this regards. Please share
Your kind support and recommendation will be highly appreciated.
Thank you
Relevant answer
Answer
Hi I'm Professor Soheil Sayyed Hosseini To solve the problem see my article on this issue of my control, motor which is published by the University of Rochester. If it is acceptable, say I wish you well.
  • asked a question related to Efficiency Analysis
Question
5 answers
Help with Stochastic Frontier Analysis in Stata, bc95 model
If you could please help me with this.
I am working on 'the determinants of health systems in Sub-Saharan Africa' and testing whether some socio-economic and environmental factors effect the efficiency of the system for my project. It is from the period of 2001-2015 and include some other countries as benchmark counties. Where Health adjusted life expectancy is my output -- my inputs are :Health expenditure, GDP per capita, ,Unemployment, Immunization of measles, diphtheria and pertussis, Access to sanitation facilities, Population density -- and my exogenous variables are: Public share of health expenditure, Out-of-pocket expenditure, Urbanization, Gini coefficient, Corruption, Government effectiveness, Rule of law.
I am using the Battese & Coelli(1995) model, where I can simultaneously parameterize the inputs and exogenous determinants of efficiency. I have gone through the Stata journal by Belotti et al. (2013) as well. I took the log of some of the inputs that were not already in % form. Every time I try and run the model I keep running into errors.
Relevant answer
Answer
My suggestion is that you can go through "A Practitioner's Guide to Stochastic Frontier Analysis Using Stata" by Subal C. Kumbhakar which will be better.
  • asked a question related to Efficiency Analysis
Question
2 answers
I have been developing the processing maps after hot deformation of a Mg-Rare Earth Alloy. The strain rate sensitivity, m, is becoming negative in some regions. Here, probably due to this, the power dissipation efficiency eta is also becoming negative.
What is the physical interpretation of this? Efficiency is a parameter that is generally defined between 0 and 1. So is its negative value wrong? What could be the reasons?
Relevant answer
Answer
Dear Neethu,
welcome,
The energy conversion efficiency is a macroscopic parameter not an intensive parameter. So, when you assess it you have to assess it in a global rather than local basis. So, it is proposed to integrate the power dissipation over the whole work piece.
Best wishes
  • asked a question related to Efficiency Analysis
Question
7 answers
scale efficiency expresses whether a firm is operating at it's "optimal size." If it is not, then using further comparisons of DEA outputs (using increasing or decreasing returns to scale) it is possible to see whether the firm is too large or too small. However, I'm confused if it's possible to conclude that a firm operating at constant return scale for long period is operating at it's optimal size? In addition, which of the return scales (INCREASING, DECREASING, CONSTANT) is a best operating condition for a firm?
Relevant answer
Answer
May be a late response but it may help at least for others.
Please refer to the book " Coelli, T. J., Rao, D. S. P., O’Donnell, C. J. and Battese, G. E 2005. An Introduction to Efficiency and productivity Analysis. Springer, New York. Page 272
it is clearly stated there and an example is done.
  • asked a question related to Efficiency Analysis
Question
10 answers
I would like to know the basic difference(s) between productivity and efficiency in spite of their being used interchangeably in many published articles
Relevant answer
Answer
Thanks a lot for your answers.
  • asked a question related to Efficiency Analysis
Question
5 answers
Looking for those that are free to access. Thank you! :)
Relevant answer
Answer
To all those who commented and gave reference, thank you very much. :)
  • asked a question related to Efficiency Analysis
Question
3 answers
For cost efficiency analysis, i ran a DEA model and a time varying panel SFA model , but i found that DEA scores are greater than SFA, and the DEAs' are decreasing during the period while The SFAs' are increasing
All the papers i read about DEA and SFA comparisons have found that SFAs' should be greater than DEAs' ,
So is there any explanation for this? could it be because of the cross-sectional nature of the DEA?
Relevant answer
Answer
I suggest you read Benchmarking with DEA, SFA, and R by Bogetoft, Peter, Otto, Lars
  • asked a question related to Efficiency Analysis
Question
4 answers
Can we check the efficiency of the Eigenvector
Relevant answer
Answer
Sure, we cannot influence on experts to get the best answer, but we can do that by another mathematical application
  • asked a question related to Efficiency Analysis
Question
4 answers
Please provide some valuable information on how to measure current density from IPCE data or graph for solar cell.
Relevant answer
Answer
Keith Fraser, Thanks for your answer. Your answer was right but the question was wrong.
  • asked a question related to Efficiency Analysis
Question
20 answers
I'm using more than 300 dmu and 12 a year period for my research. I tried to do this with stata and DEAP 2.1 as well but it takes a long time, however, at the final stage I did not get the result fully (not showing the full result for stata, I used only 100 dmu for 1 year). Can anyone tell me how to handle large sample for DEA?
Relevant answer
Answer
If you have zero or negative value in input and/or output values you will not be able to see the results in the output files. You better remove the zero or negative values from your dataset. Thank you.
  • asked a question related to Efficiency Analysis
Question
5 answers
DEA software for bootstrapping
Relevant answer
Answer
Dear sir,
You can use Stata, Eviews and Shazam to run Bootstrap.
But there's the point that with this software you can not get the corrected bias estimators for each DMUs.
So, I suggest using the Excel software. In this software, you must use the correct command to get the corrected bias estimators and then try to estimate the distances.
  In the this regard, I sent you an attachment file that can help you with this.
I hope it could help...
Alireza
  • asked a question related to Efficiency Analysis
Question
3 answers
In the eighties, as part of my standard marketing training, I learned a technique designated Frontier of Efficiency Analysis as applied to product pricing.
I looked for references to this to be sure that I correctly recalled the definitions and terms before investigating its application in an alternative process.
All the references I find lead to work derivative from Markowitz who used a similar term on the evaluation of portfolios. This is not what I need.
Can anyone help / recall work in its application to product pricing?
Relevant answer
Answer
Thank you all for your answers.
The technique I recall was considerably less mathematical / rigourous and dealt with how buyers optimise perceived value on multi-criteria. Perhaps the maths underlying Markowitz efficient frontier theory could have made it into a more rigorous technique.
I've concluded the best approach is for me to document what I recall (a very Amos and Andy technique) and see if anyone recognises it.
@Greg thank you. Perceived value is the key and I plan to link this to buyers' formal evaluations of bidders' offers in B2B competitions
  • asked a question related to Efficiency Analysis
Question
5 answers
Hi, 
I am interested in doing FISH on leukocytes in a single cell suspension so that they can be analyzed via FACS.  If effective, this would allow for more efficient analysis and of many more cells than traditional FISH-fluorescent microscopy (a method I have previously used with success).  
Protocol: 
1) Cells fixed with Carnoy's in a drop-wise manner. Spin, decant supe.
2) Permeabilize cells with 0.1% Igepal in 2X SSC. Spin, decant supe.
3) Resuspend cells in hybridization buffer (70% formamide 2x SSC).
     a) Co-denaturation: Expose cells and probe to 75C for 5' together. 37C o/n
     b) Separate denaturation: Cells 72C for 5' and Probe 90C for 10'.  37C o/n
     c) Separate denaturation: Cells 37C for 5' and Probe 90C for 10'.  37C o/n
4) Wash with 0.1% Igepal in 2X SSC. Spin, decant supe.
5) Preheat 0.3% Igepal in 0.4X SSC to 72C.  Add buffer to cells expose to 72C for 2'. Add equal volume ice cold PBS. Spin, decant supe.
6) Resuspend in PBS.
At this point I'm not attempting FACS,  I am cytospinning on to slides until I optimize the hybridization conditions.  I have given it a couple passes and I am routinely running into the same issues: 
1) Enlarged nuclei, (the nuclei appear to be large and have a more diffuse DAPI signal). The nuclei seem to denature/enlarge once exposed to 70% formamide 2x SSC independent of heat.   Possible problems: inadequate fixation, absence of graded alcohol dehydration steps like in traditional fix.
2) Ineffective hybridization.  Since the conditions used have successfully worked for traditional FISH it would seem they should work.  Also probably a inadequate fixation or denaturation issue.
3) Cell clumping.  Cellular denaturation is resulting in the 'netting' of cells by DNA strands after exposure to 70% formamide 2x SSC.  
I have some ideas of what to try next, but if anyone has had previous experience with Flow-FISH and could provide insight that would be great.
Thanks!
Relevant answer
Hey Steven,
I know it's been over a year, but if you're still interested, take a look at the PrimeFlow kit from thermo. https://www.thermofisher.com/us/en/home/life-science/cell-analysis/flow-cytometry/primeflow-rna-assay.html
  • asked a question related to Efficiency Analysis
Question
9 answers
  a
Relevant answer
Answer
Hey Ehsan, 
you can check a paper by Lai and Huang "Maximum Likelihood Estimation of Seemingly Unrelated Stochastic Frontier Regressions"
Hope it helps. 
Good luck
  • asked a question related to Efficiency Analysis
Question
1 answer
In incorporating risks into efficiency analysis in agriculture, what approaches are employed in quantifying and estimating the related frontiers?
Relevant answer
Answer
Non-parametric linear programming approach can be used.
Please refer to the article:
"Incorporating Risk in Efficiency Analysis " by Saleem Shaik and Glenn A. Helmers 
at
Good Luck.
  • asked a question related to Efficiency Analysis
Question
1 answer
I need the sintaxis required for that macro, in order to proceed.
Relevant answer
Answer
Please refer to the website
You will see all the necessary steps such as
GET FILE =‘C:\PISA\DATA2006\All.sav’.EXE
  • asked a question related to Efficiency Analysis
Question
28 answers
In Differential Scanning Calorimetry Testing (DSC) can we use liquid sample like some oil or waxes? Thermal efficiency analysis 
Relevant answer
Answer
Of course it is possible to test liquid samples in hermetic closed sample pans in a DSC. There is no problem to see transitions, melting and Tg for such substances and to measure the heat capacity. You should however take care to be enough away from the boiling point to avoid burst of the pan. Furthermore you should test the tightness of the pan by comparing the mass before and after the run to see whether possible evaporation has occurred. I usually tested the liquid substance in the same temperature range in a TGA first to see whether there are components in the liquid which would evaporate at elevated temperatures. The heat of evaporation could possibly lead to a falsification of the DSC result. Good luck!
  • asked a question related to Efficiency Analysis
Question
5 answers
I am using different university departments in an efficiency analysis using DEA. syllabuses and evaluation procedure are different in different units. do I need to standardize the tests scores separately for each department.
Relevant answer
Answer
But Asela, If he uses different frontiers for the various groups he cannot compare the efficiency scores since the assumption of technological heterogeneity is then automatically assumed. The best he can do when different frontiers are used is by conducting a Metafrontier or Global frontier analysis
  • asked a question related to Efficiency Analysis
Question
3 answers
How do we calculate the efficiency of a HPGe in percentage.
Relevant answer
Answer
  • asked a question related to Efficiency Analysis
Question
2 answers
How can I evaluate efficiency of a H-bridge driven DC machine under different control methods? I can measure input voltage and current of H-bridge and output speed and torque produced on the shaft of DC machine (I have torque transducer). I have samples of all variables every 50us. 
I want to evaluate actual efficiency during chosen interval. When evaluating efifciency as (output power / input power), zero samples are causing a problem. Should I use moving average filter for all variables in order to avoid zero samples? 
Relevant answer
Answer
Hi Karol,
The longer you can wait, the better it goes - as a matter of fact :-)
Recall the filter dynamics I mentioned in my first reply ? They will progressively decay as you wait !!
You can go for higher order MA filters, but I doubt if they will be of additional use in any way !
  1. You already know what is the operating cycle of your H-bridge, and I don't think you propose to tamper with that ?
  2. The higher the MA order you choose, the slower will be the decay of the filter dynamics. So you will have to "wait longer" for correct results !
Cheers !
-Sanjay
  • asked a question related to Efficiency Analysis
Question
6 answers
HI I am working on monopole antenna. But I experience one thing that when I increase the ground size to 3*lmbda or more i get total efficiency of the antenna greater than 100% which is not possible. When I decrease the ground plane size the efficiency is less than 100%. Can you please suggest me why this is giving efficiency greater than 100%?
Relevant answer
Answer
Are you using software or measurements?
  • asked a question related to Efficiency Analysis
Question
1 answer
when using malmquist.components routine in the FEAR package (R program).
Relevant answer
Answer
I am not familiar with the FEAR package, but in response to your question there is  a very general and short answer. Simply use square matrices, with each column and each row in turn having a specific order, pertaining to the same (role-playing) entity.
  • asked a question related to Efficiency Analysis
Question
5 answers
high conversion efficiency in my idea is sth more than 14%
Relevant answer
It contains also one step fabrication of the pervosite layer that can be used with other pervosite solar cell structures!.
  • asked a question related to Efficiency Analysis
Question
13 answers
Hello all,
I am working on estimating the technical, cost and total efficiency of some ten school districts using Data Envelopment Analysis in Stata. I have two input variables - teacher salary and number of teachers; and one out variable Math Score of students. I am using the output-oriented variable returns to scale (vrs) option. This gives me the theta values and crs, vrs, nirs and scale efficiencies. Can I consider the theta values as the total efficiency score? And how do I get the cost efficiency values?
Any suggestion as to how to code or point me to a help source would be very much appreciated. Thank you in advance!
Charles
Relevant answer
Answer
The table above shows Technical Efficiency (CRS_TE), Pure Technical Efficiency (VRS_TE) and Scale Efficiency (SCALE). CRE_TE = VRS_TE * SCALE. None of them indicates total efficiency as you expected. I've never calculate DEA with Stata but in my opinion you might pick the wrong model.     
  • asked a question related to Efficiency Analysis
Question
14 answers
I did efficiency analysis using Data Envelopment Analysis (DEA) and I am using these efficiency scores as a dependent variable. My independent variables are farmers' socioeconomics (age, education, farming experience, family member is farming, area under cotton) and institutional variables (access to extension, credit and market). 
I have applied truncated regression, censored regression and Tobit model. But each of these models does not give many significant variables and most of the signs are negative too, except education. So, where am I doing wrong? Is the model selection not appropriate or there isn't necessarily a relationship among these variables? I found in literature, many researchers have found significant relationships using these models. 
Any useful comments will be highly appreciated. 
Relevant answer
Answer
Farhard. As I understand, you are first deriving efficiency scores using (some conceptual input-output model and) DEA method and then you use those scores as dependent variable in some other model in order to assess determinants of efficiency. This is known to be a two-stage approach. Wang and Schmidt (2002) have shown that such two-stage approaches to analyzing determinants of efficiency differences are seriously biased. See their article for alternatives (one-stage approaches). You can also see Battese and Coelli (1995) or, a more advanced approach by Koop, Osiewalski and Steel (2000; Journal of Business & Economic Statistics).  It does not mean that everything is ok with your choice of variables and/or number of observations you have (DEA is a nonparametric method, thus results are more depended on data quality and sample size, which is often too small in empirical applications of DEA) but without addressing the "two-stage" problem you are unlikely to get anything valid out of this. 
Hope this helps. 
  • asked a question related to Efficiency Analysis
Question
2 answers
I am running the SBM model using the package "DJL" in R. Although it was fine, when I changed my model's input variable, almost all the DMUs turned to be zero efficient and a few got a efficiency index equals 1. Do you have any suggestions or conclusions about that?
I found it quiet weird because it semmed to be ok before.
Thank you. 
Relevant answer
Answer
thanks you!
  • asked a question related to Efficiency Analysis
Question
4 answers
Hi, I want to measure how the variable X affects the way Y is efficiently used to generate the outcome Z. 
Y is an acknowledged enabler of Z, and I want to verify whether X is able to improve Y  beneficial effect. 
I would use DEA (output oriented, VRS) to assess the extent to which Y is used efficiently to generate Z (step 1), and then use the efficiency values of the DMUs as dependent variables in a regression with X as a independent variable (step 2).
Here is the question: Y is NOT the only input of Z, but i wouldn't add any other in order to avoid "rumor". I would add other independent variables that are likely to influence Z in step 2 regression.
Will this make the output of the DEA virtually useless or meaningless due to the small part of Z explained by Y?
Hope I've been clear, thanks for helping!
Relevant answer
Answer
Marco,
I think you need to read a lot more on production and efficiency analysis.
Finding a significant effect of X on efficiency scores from Z~f(Y)-u indicates that X DOES have a significant effect on Z conditional on f(Y). If you look at the equation in the previous sentence (u is inefficiency) you can see how this comes about. Thus, you would be generating an omitted variable bias by doing this.
I would suggest including ALL relevant variables in the regression and none in the second stage. include them as 'fixed inputs' and analyse their effect on the intercept term. However you are doing DEA so i guess your main interest is the 'secondary regression' for inefficiency effects. In this case you need to include all relevant production variables in the DEA - not doing so simply means that what you are allocating to 'inefficiency' is simply omitted variables in the production function. 
Now if you really did want to generate a one input, one output DEA model this is the simplest linear program ever - simply divide output by input for each observation and sort them. the highest one is your ONLY 'efficient' firm (maybe you find equal highest scores though). By dividing all ratios by the ratio for this efficient firm you will get 'efficiency' scores. Note that this is akin to using a partial productivity measure when there are other inputs available. You could possibly aggregate outputs and inputs into single indices using a proper index (see Chris O'Donnell's Journal of Econometrics 2011 paper) and then do this approach which would make more sense i think if that was the case.
Good luck. Happy to be corrected as always.
Daniel
  • asked a question related to Efficiency Analysis
Question
2 answers
Hello all,
I have been trying to differentiate P19Cl6 cells into cardiomyocytes. However the efficiency is quite low. I know that serum plays quite important role for the process. Do you have any suggestions about that? So far, I tried almost every FBS version of Gibco and none of them worked better for me. 
Thank you very much for your help in advance
Relevant answer
Answer
Hi Ulrike,
I am just checking the paper. Thanks a lot.
  • asked a question related to Efficiency Analysis
Question
7 answers
By combining stochastic frontier and copula function it's possible to relax two main strict conditions of standard SFA. These regard the normal distribution and the independence of inefficiency and the pure randomness component.It is possibile to prove that if these two components are dependent and follow distributions other than normal, then the estimated efficiency scores are highly biased, thereby implying that past efficiency literature might be wrong.
If you are using (or if you have used) standard frontier approach (e.g., à la Battesi and Coelli 1992 and 1995) you can provide us your dataset and write a joint paper based on the re-specification of your model.
Data may refer to any sector.
Comments welcome
Relevant answer
Answer
Yes. Just returned the corrected proof to the publisher. I have sent you an email from dgameli2002@gmail.com. You may check your spam (junk) mail folder if you d not fund it in the inbox.
  • asked a question related to Efficiency Analysis
Question
3 answers
what is the appropriate formular for this effciency measure?
Relevant answer
Answer
TFP indices very generally are the differential growth rate between aggregate output and aggregate input quantity.  If you have a quantity measure of output growth, subtracting total input growth gives TFP..  The challenge becomes with multi-output and multiinput and price differences.  Indices, such as the Tornquist/Divisia indices, are generally derived from assumptions of efficient/competitive input and output markets, and cost minimising producer behaviour.  In general, if every output gets paid it's efficient/competitive price, and every input the same, then the revenue-value shares are the 'weights' to form the aggregate output growth rate 'cost shares' are the appropriate input 'weights' to form the weighted average input growth rate.  Other indices can get more complicated, such as based on distance functions, etc, but the essence is always some need to form a method of aggregation and take the differential growth rate between output and input.  The references by Faris's cite are also good.
  • asked a question related to Efficiency Analysis
Question
6 answers
Can anyone researcher help me in calculating Drug Encapsulation Capacity and Efficiency.in nanoparticles?
Thanking in advance.
Relevant answer
Answer
Both efficiency and capacity are one or other way same. Based on method adopted, ratio of core-coat, experimental conditions such as stirrer rotation speed, temperature etc., the encapsulation efficiency will vary. But, surely drug content estimation and drug encapsulation efficiency are different.
  • asked a question related to Efficiency Analysis
Question
2 answers
I the last decade or so, research focus has shifted from policy implementation and administration to that of measuring efficiency and effectiveness of public sector in respect to performance.
In this context, measuring efficiency and effectiveness in public sector organization is key in my research. My main research focus at this point in time is to design set of metrics to measure efficiency and effectiveness in the Nigerian public sector.
Relevant answer
You have firstly to take indicators of public service coverage in your country, then through a participatory planning process, decide the annual increase, allocate budget resources, and at the end of the period you have to look for results, and then define the following: 1) Degree of utilization of resources is Utilized Budget divided through by Approved Budget; 2) Efficacy is Goals achieved divided by Goals Programmed; and 3) Effectiveness is Efficacy divided through by Degree of Utilizations of resources. Hope this will be useful.
  • asked a question related to Efficiency Analysis
Question
3 answers
I wrote a GAMS code for a non-radial DEA model i.e. a multiplier Slack Based Model (SBM) with undesirable outputs, presented by WEI et al. (2012). Why do the model results in negative scores, despite the set Constrains 1(j) (see the GAMS code)?! Where did I go wrong? I attached the required files.
Thanks in advance.
Wei, C., Ni, J., & Du, L. (2012). Regional allocation of carbon dioxide abatement in China. China Economic Review, 23(3), 552-565.
Relevant answer
Answer
Due to elimination of a variable, the efficiency scores are actually 1+E, where E is a negative number resulting from the linear problem in the paper. See Section 13.2.2 in Cooper, Seiford, and Tone (2006).
  • asked a question related to Efficiency Analysis
Question
25 answers
I used sfcross command to estimate stochastic frontier of production function.
The example of STATA command :
sfcross lnYield lnLand lnChemfer lnLaborloc lnMachineryh if Typology==0
predict e,u
I wonder if the value of e represent the technical efficiency? I really doubt it.
Relevant answer
Answer
Hi  Yousuf, 
The easiest way is:
1) Open STATA
2) Choose "Statistics" from the menu
3) Choose "Linear models and related"
4) Choose "Frontier models"
5) Once you have opened it (Frontier models), you can see "Model 1" where you specify the production function variables, and "Model 2" you specify variables explaining the inefficiency.
Once you run the model, Technical Efficiency coeff are obtained with the command , predict te, te
Good luck!
Gordana
  • asked a question related to Efficiency Analysis
Question
1 answer
I would like to know if there is any study assessing the efficiency of clinical research conducted in private research center vs universities or public/governmental research centers.
I am looking for comparison of: patient retention, cost, time from initiation of the study to completion of the study, time from initiation of the study to publication of the findings, time from initiation of the study to FDA approval.
This can apply to any type of research: medical or dental, social, engineering etc.
Relevant answer
Answer
Hello, there is surely something published on the subject you're looking for, I recommend a systematic review on the following link, luck and greetings.
  • asked a question related to Efficiency Analysis
Question
17 answers
I new some variables to include in measuring teacher efficiency.
Relevant answer
Answer
Before one can measure a complex concept like this, one would need to define as clearly as possible the various dimensions involved. Efficiency at doing what?  A starting point might be to assemble a group of people, including teachers, students, school administrators ... to discuss what meanings they attach to the term.
A next step would be to clarify the question, efficiency as perceived by whom?  A student's perception of a teacher's efficiency might be based on observations of lessons, speed with which homework is corrected and returned.  A teacher's self perception of his/her efficiency might be based on some other criteria. A school principal's perception of a teacher's efficiency might be based on submitting curriculum plans, test results, school reports etc on time to meet school-determined deadlines.
How to measure these various dimensions is a later question. Various methods may well be useful. Summated rating scales could be used to measure student perceptions. Observations by trained observers over a few lessons could be used to assess practical teaching skills. Open-ended questions put to a school principal might be a useful source of information.
In short, I would doubt whether the concept could be reduced to a single score, as the three  previous respondents to this question have already wisely pointed out.
  • asked a question related to Efficiency Analysis
Question
5 answers
I am interested to investigate the relationships of sense of home and building efficiency in housing context. I think the effect of sense of home in improving individuals' behavioral and emotional pattern would eventually affect the building efficieny. I appreciate a lot if anyone can help me by introducing papers and research works in this area.
Relevant answer
Answer
For this you need to look at the building in the context of socio-cultural and socio-economic point of view. What you mean is that if two similar building (built up area, building material, internal arrangement of rooms etc.) occupied by two family will reflect different efficiency. This happens because the family which find the building that satisfies their socio-cultural and socio-economic status will tend to feel less irritated and show high level to tolerance thus showing high level of comfort( low energy use to maintain comfort). In my publication I tried to highlight this issue. If interested you can read my papers on "Bioclimatism and vernacular architecture" and "Relation between indoor thermal environment and renovation in Liege residential buildings"
regards
  • asked a question related to Efficiency Analysis
Question
11 answers
I am interested to estimate technical efficiency based on Battese and Coelli (1992) model. I have tried many times for the estimation both using the command prompt as well the use of instruction file in Frontier 4.1. But the dialog box immediately disappear once I end up the process by giving the command through running the FR0NT41 .EXE. Could anyone guide me where is the problem and how could i estimate it.
Relevant answer
Answer
Dear Auro,
I think that there might be an inconsistency between your ins file and the txt file used by the program in order to read the data. If you are not already using R and still want to try on Frontier, send me the .ins file and the .txt file containing the first two or three rows of your data in order to check it on my computer.
Regards
Spyros
  • asked a question related to Efficiency Analysis
Question
4 answers
What are the parameters which influence vehicle performance in terms of fuel consumption [Gas Consumption] ?
For Eg : Air density , road terrain , atmospheric conditions influence vehicle performance in terms of fuel consumption [Gas Consumption] 
I want to know are their any other major,minor factors that i have missed which influence fuel consumption.
Relevant answer
Answer
There are many parameters, not all of which are obvious, and the best way to start is to look at the complete system. From inside out:-
  • Powertrain characteristics:- Specific fuel consumption at various loads / speeds and transients, gear ratios, overall system efficiencies, etc.
  • Product characteristics:- Weight (inertia, both translational and rotating), aerodynamics, parasitic loses (tyres, bearings etc.), other loads (battery charging, air conditioning etc.)
  • Drive cycle:- how is the product being used (short trips, long trips), with what payload, who is driving (sporty and aggressive / smooth and economical), time of day (congestion), speed limits, gradients, windows / sunroof open or closed, etc.
  • Environment:- Fuel quality, air quality, temperature, altitude (air density), road smoothness / surface, wind speed and direction etc.
As you can see there are many variables ( the list is not exhaustive but provides a framework) which combined in different ways give an almost infinite variety of outcomes, hence two people making the same journey in the same car can be 10% or more different in fuel consumed. This is the reason (a) for standardised testing for Government Fuel Economy figures, (b) why real world fuel consumption will be markedly different.
  • asked a question related to Efficiency Analysis
Question
8 answers
I should solve a DEA CCR or BCC input oriented model. All data are considered as outputs and there is no inputs (objective function is maximizing the outputs). With LINPROG in matlab we need Aeq and Beq. Should we add a virtual input? or a unit vector as our only input?
Relevant answer
Answer
Hi Elame, I think she meant not to use inputs, but just outputs (as I also expect to use). I think the model you are talking about uses both inputs and outputs, however aims to maximise efficiency by changing the weights in the outputs and keeping the weights of inputs unchanged. If we use just outputs, we just assign an arbitrary single positive integer (e.g. 1) to act as the same denominator for all DMUs. Please correct me if I am wrong.
  • asked a question related to Efficiency Analysis
Question
5 answers
what is the difference between measuring performance and measuring efficiency using Pabon Lasso model?
Relevant answer
Answer
PABON LASSO MODEL: It is a technical efficiency (TE) measurement based on performance. These two terms go hand-in-hand in this model. PL Model is a graphical representation where Y = BTR (bed turn over rate) and X = OCC (occupancy rate). BTR and OCC are performance measurement.
PERFORMANCE MEASUREMENT USED: The performance measured used in PL include:
(1)  ALS = inpatient days / admissions
This measures the average number of days the patient stays in the hospital. 
(2)   OCC = (patient days / bed days) 100
This is the measure of utilization of beds available bed capacity.
(3)   BTR = total patient admissions / number of beds
This measures the productivity of hospital beds. These three measures are performance measurements. When they are put into PL plot, it allows the hospital to analyze its technical efficiency.
EFFICIENCY: Efficiency measurement generally involves the use of frontier analysis. The outer limit of the frontier is the expected value against which the performed value is compare. A ratio of 1:1 is the most ideal, but difficult to achieve. This the closer to that ratio is the goal. In PL model the coordinate of the plot of Y = BTR and X = OCC is divided into 4 quadrants. Quadrant III is ideal and I is the most inefficient. See attached figure.
  • asked a question related to Efficiency Analysis
Question
2 answers
Can anyone advise on how to carry out sensitivity analysis in DEA using any freely available software like EMS or Max DEA or any other?
Relevant answer
Answer
There are two directions of analyzing the sensitivity of DEA efficiency scores :
1. Sensitivity analysis of model changes  : basically you are trying to assess if using different input and output variables changes the DMUs' efficiency classification. This exercise basically allows you to see what effect of different input/output variables have on the DEA results. I think this analysis is heavily driven by the theory of production specific to each industry. You do not require any specific software to do this.
2. Sensitivity analysis of data variation : This form of analysis assess what effect would you see if the sample/population of the DMUs change. Since DEA is a non-parametric approach and unable to separate data noise from signal, any outlier and data errors will cause the DMUs to be reclassified (as efficient/inefficient). The common way of doing so will be to manually test for excluding outliears from the sample or doing some bootstrapping DEA. I use R to do this. Two packages in R is good for this : Benchmarking and FEAR packages. They have their respective strength and weaknesses
  • asked a question related to Efficiency Analysis
Question
3 answers
I would like to use a Data Envelopment analysis (DEA) model in which one input is a probability value and one output is an expected value (whose value depends on the probability value used as input). In such a situation, should be the case to use the chance-constrained DEA? I know that it can use when inputs and outputs are random variable with a known probability distribution. However, in my case, I have as a input a probability value.
Thank you very much
Relevant answer
Answer
ISSUE: How to deal with expected value of output and probability of input in DEA model?
BASIC MODEL: Data Envelopment Analysis (DEA) is a nonparametric tool tool for efficiency measurement. Productive unit efficiency is obtained by the weighted sum of outputs divided by the weighted sum of inputs, thus:
(1)   E = (ΣUiYiq) / (ΣVjXjq)
... where V = weight assigned to j-th input; and U = weights assigned to output. For short (1) may be written as E = A / B. You question asks how to deal with this situation:
(2)   E* = A^ / Pr(B)
... where A^ = a-hat is the expected value of A; and Pr(B) is the probability of B. Output depends on input; therefore, the expected output depends on the input factor is not a problem. What to make of the "probability of input?" It appears that Pr(B) where B is already weight-times-input matrix is an application of Kahneman-Tversky's Prospect Theory where:
(3)   U = Σw(Pi)v(Xi)
... where w = eight; v = function that gives the possible outcome; and Xi = observed outcome; and Pi = respective probability of each observation. Recall that B = (ΣVjXjq) or B = sum of weight-times-input. This is equivalent to w and Xi in Kahneman-Tversky and Pr(B) is Kahneman-Tvertsky's U.
Why is you output written as "expected value of output"? It must be written as "expected value" because you do not have a "real input" value, but a probability of that value.
Therefore, you do not have a problem and you do not need to do any conversion or scaling. This is a matter of the use of formal language, i.e. formal statement, of condition in mathematics. Continue with your analysis as if you have to deal with a straight forward equation (1). The logic for the expected output and probable input is found in (3).
REFERENCES: I attached here 2 articles that might be helpful: (i) DEA modeling, and (ii) Propspect Theory by Kahneman-Tvertsky. I hope this has been helpful. Cheers.
  • asked a question related to Efficiency Analysis
Question
2 answers
As the capture antibody is mouse antihuman, I suppose I will need to use antiseptics detection antibody such as rabbit anti mouse, goat anti mouse. I could infer this from answers I received previously on this site and also from some other sources.
I am writing now to request suggestion on some recommended detection antibody/ies appropriate for the above mentioned capture antibody. Thanks. 
Relevant answer
Answer
Thanks Ana. I am developing luminex sandiwich immunoassay and my question was to ask for the most effective pair of capture/detection antibodies.
  • asked a question related to Efficiency Analysis
Question
3 answers
I have programmed 2D magnetotelluric forward modeling using both finite difference and finite element method . i want efficiency analysis of these pregame. What is the best way to do this ?
Relevant answer
Answer
I think there are not considerable  differences between two methods Finite Difference Method and Finite Element Methods , for the same nets of points in case of the 2D geometry. The differences are considerable in the case of 3D geometries. In the last case with the FEM methods, you will receive more accurate results.   
  • asked a question related to Efficiency Analysis
Question
5 answers
I prefer to use ratio or percentage, as this way takes care of the issue of unit measure or size of input/output.
Relevant answer
Answer
In addition to Sergio's answer, note that ratios and fractions as inputs or outputs in the production set also invalidates the use of CRS or NDRS, you are forced to use FDH or VRS. 
yours
pja
  • asked a question related to Efficiency Analysis
Question
9 answers
Is inefficiency one of the inherent properties of complex systems or does inefficiency lie in the eyes of beholder? 
Relevant answer
Answer
This is a good and non-trivial question. The answer will definitely depend on the actual definition of the 'efficiency'. One possibility is to take physics approach and calculate system's thermal efficiency. Second law of thermodynamics sets limits on such efficiency. But in the general context of adaptive complex systems there is no simple way to calculate 'efficiency'. Such systems are usually far from equilibrium and simple equilibrium considerations do not hold. Such systems are also open in the sense that they interact with the environment, using the energy from outside to lower their entropy. The more 'complex' these systems are, the better they become at this process of using external energy to lower their entropy - this appears to be a way to see complexity of adaptive complex systems. But strictly speaking, their thermal efficiency is lower than that of the reversible ideal heat engine. And I believe that the more complex - the more irreversible and the more (thermally) inefficient the systems are. But it is up to you how you define efficiency and in turn, how you interpret the increase of the adaptive properties of complex systems. Please check this article which in easy terms discusses some of the relevant concepts and highlights some fairly recent advances: http://www.quantamagazine.org/20140122-a-new-physics-theory-of-life/
  • asked a question related to Efficiency Analysis
Question
3 answers
I am thinking of encapsulating a hydrophobic antioxidant (lets call it A) using a spray dryer.
Since it is hydrophobic, i was thinking of dissolving A with a vegetable oil, maltodextrin as a wall material and gum arabic as surfactants in water. This emulsion is then spray dried.
However, I am not too sure how to determine encapsulation efficiency. Any advice?
*sadly i do not process a spray dryer capable of handling solvent.
Relevant answer
Answer
Sure there are other ways. You can check which is a good solvent for your compound (ethanol, methanol, usually work well for hydrophobic phenolics, but I don't know the entity of "A"). 
First of all you have to extract A from the encapsulating matrix. You can try to do it directly in the solvent, however maltodextrin can be tough to release its cargo when  it is dispersed in a non polar solvent. One possibility to tackle this is to grind the capsules very well prior to the extraction and to do the extraction for a long period. 
Consider also where would you want A to be released (if you encapsulate it, I guess you want to release at some point). In that case what you can do is to perform release experiments in the medium that your are interested, i.e., water at a certain pH (no matter if it is acqueous phase, aftwerwards it has to be released there) and then measure how much is actually released to that medium. At some point there will be equilibrium, and the maximum amount that is released can be considered for calculating and "Effective Efficiency Ratio". Meaning that even if you have more compound encapsulated inside, it won't be released, so you can consider it "lost".
If you really want to calculate how much is encapsulated, though, the most accurate thing to do is thermogravimetric analysis (TGA). You can read further about it, there is plenty of information online and probably someone in your university has one TGA instrument (Chemistry or Chemical Engineering Departments usually do).
Remember you are encapsulating an antioxidant, so instead of measuring the concentration (for example with chromatography), you can use the classical Folin, DPPH, ABTS or any other simple in-vitro antioxidant capacity test!
Now good luck with your experiments!!
  • asked a question related to Efficiency Analysis
Question
8 answers
How to improve solar cell efficiency?
Relevant answer
Answer
8 PrintedOrganicSolarCells
ClaudiaHoth1,AndreaSeemann1,RolandSteim1,Tayebeh Ameri2,HamedAzimi2andChristophJ.Brabec
For better understanding of efficiency obstracles and limitation read the above givn book chapter it will help you to understand the concept
  • asked a question related to Efficiency Analysis
Question
3 answers
I rarely read of it's use in papers - is it problematic/does it complicate the picture?
Relevant answer
Answer
.
it is of course desirable to have just one aggregate combining both error rate and time to respond ...
but ...
being an aggregate, it may of course hide some fine and relevant structure in the interaction between its components
(the same could be said for F-score in information retrieval)
and do **not** use IES if you suspect some possible accuracy/speed trade-off in your experiments !
see for instance :
.
  • asked a question related to Efficiency Analysis
Question
22 answers
I'm going to run second stage for banking efficiency using Tobit Model. I need to find out the determinants for banking efficiency. Other than the Tobit Model, is there any other model I can use?.
Relevant answer
Answer
Dear Syamsulang
the McDonald paper that has been indicated is an important one, but there is some debate on this issue. You should definitely take heed of a couple of contributions mainly advocating truncated regression at the second stage:
Simar, L. and P. W. Wilson (2007), ‘Estimation and inference in twostage,
semi-parametric models of productive efficiency’. Journal of
Econometrics 136, 31–64.
Simar, L. and P.W.Wilson (2011), ‘Two-Stage DEA: Caveat emptor’.
Journal of Productivity Analysis 36, 205–218.
As you'll see there is a delicate assumption of separability when relying on second-stage regressions.
There is a quite useful paper by Johnson on this matter, which I only know as a mimeo: http://www.flinders.edu.au/sabs/business-files/staff/mcdonald/1.pdf, that can help you to make your mind about these issues.
Best
S.
  • asked a question related to Efficiency Analysis
Question
18 answers
I am trying to perform a congestion analysis, using R (benchmarking package). I would like to calculate the TE under these 2 different assumptions. After going through dozens of papers, I am still confused as to how the TE ratio can be calculated. Looking at the Benchmarking package, I don't see any specific function for this purpose. Appreciate if any DEA experts can provide some insight.
Relevant answer