Publications (10)25.59 Total impact
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Conference Proceeding: A determination coefficient for Fuzzy Random Variables in a fuzzy arithmetic-based linear model
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ABSTRACT: A natural way of quantifying the degree of linear dependence between two fuzzy random variables in certain models is analyzed. In these models, the linear relationship is formalized in terms of a regression model based on the usual arithmetic for fuzzy sets. The degree of linear relationship is proposed to be measured by means of a kind of determination coefficient, that is, through the proportion of variability of the response fuzzy random variable explained by the regression model. Some properties of both the models and the determination coefficient are analyzed in order to verify the suitability of this coefficient as a measure of linear dependence. Finally, the meaning of a correlation coefficient which mimics the usual one for real-valued random variables is discussed.Fuzzy Systems Conference, 2007. FUZZ-IEEE 2007. IEEE International; 08/2007 -
Article: Prospective randomised phase II study of docetaxel versus paclitaxel administered weekly in patients with non-small-cell lung cancer previously treated with platinum-based chemotherapy.
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ABSTRACT: Docetaxel and paclitaxel have activity in the second-line treatment of non-small-cell lung cancer (NSCLC), and can be administered as weekly schedules. This phase II randomised study was designed to test the efficacy and toxicity of both taxanes in patients with NSCLC previously treated with platinum-based chemotherapy. Patients (n = 71) with documented NSCLC were randomised to receive docetaxel (n = 35 patients; 36 mg/m(2)) or paclitaxel (n = 36 patients; 80 mg/m(2)) as a 1 h weekly infusion for 6 weeks followed by a 2-week rest. The cycles were repeated until disease progression or non-acceptable toxicities occurred. Treatment achieved partial response of one versus five patients, median time-to-progression of 74 versus 68 days, and overall survival of 184 versus 105 days, with docetaxel and paclitaxel, respectively. The most common non-haematological toxicities were (docetaxel versus paclitaxel): grade 3/4 pulmonary toxicity in seven versus one patient; grade 2/3 diarrhoea in nine versus five; and grade 3/4 haematological toxicities occurred in two versus four patients. There were no treatment-related deaths. Docetaxel and paclitaxel administered weekly have discrete efficacy in patients with NSCLC previously treated with platinum-based chemotherapy. The higher non-haematological toxicity of docetaxel, particularly pulmonary toxicity and diarrhoea, is of concern and warrants further investigation.Annals of Oncology 12/2003; 14(11):1640-7. · 6.43 Impact Factor -
Article: Phase III trial of cyclophosphamide, epirubicin, fluorouracil (CEF) versus cyclophosphamide, mitoxantrone, fluorouracil (CNF) in women with metastatic breast cancer.
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ABSTRACT: The mitoxantrone combination CNF and the epirubicin combination CEF have shown similar activity and less toxicity than the standard CAF combination in metastatic breast cancer (MBC). A prospective randomised study was started to compare safety and activity between CEF and CNF administered using a classical chemotherapeutic schedule in MBC. From December 1987 to June 1993, 151 patients were randomised to receive cyclophosphamide (C) 100 mg m(-2) p.o. days 1-14, fluorouracil (F) 500 mg m(-2) i.v. days 1 and 8, and epirubicin (E) 30 mg m(-2) i.v. days 1 and 8, or mitoxantrone (N) 6 mg m(-2) i.v. days 1 and 8, every 4 weeks. Seventy-three patients were eligible for CEF and 72 for CNF. Objective responses were observed in 61.6% of the CEF group and 44.4% in CNF group (p = 0.004). The median duration of response was 64 weeks in CEF and 50 weeks in CNF group (p = 0.02) and median time to progression was 51 and 33 weeks, respectively (p = 0.0004). At the time of analysis, all except six patients (one in CNF and five in CEF) had died and the median survival time in the CEF group was longer than in CNF (74.4 weeks vs 51.4 weeks; log-rank chi2 test p = 0.015). CNF produced more hematologic toxicity than CEF (WHO scale; grades 2-4); leucopenia 84% vs 68% (p = 0.03) and thrombocytopenia 17% vs 4.5% (p = 0.01); CEF caused more grade 2 and 3 alopecia: 93% vs 70% (p = 0.001). The combination CEF using this schedule and dosage in metastatic breast cancer is more effective with less toxicity than CNF, except for alopecia, and was associated with longer survival.Breast Cancer Research and Treatment 12/1999; 58(2):141-50. · 4.43 Impact Factor -
Article: Phase III trial of cyclophosphamide, epirubicin, fluorouracil (CEF) versus cyclophosphamide, mitoxantrone, fluorouracil (CNF) in women with metastatic breast cancer
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ABSTRACT: Background: The mitoxantrone combination CNF and the epirubicin combination CEF have shown similar activity and less toxicity than the standard CAF combination in metastatic breast cancer (MBC). A prospective randomised study was started to compare safety and activity between CEF and CNF administered using a classical chemotherapeutic schedule in MBC.Patients and methods: From December 1987 to June 1993, 151 patients were randomised to receive cyclophosphamide (C) 100mgm–2 p.o. days 1–14, fluorouracil (F) 500mgm–2 i.v. days 1 and 8, and epirubicin (E) 30mgm–2 i.v. days 1 and 8, or mitoxantrone (N) 6 mgm–2 i.v. days 1 and 8, every 4 weeks. Seventythree patients were eligible for CEF and 72 for CNF.Results: Objective responses were observed in 61.6 of the CEF group and 44.4 in CNF group (p=0.004). The median duration of response was 64 weeks in CEF and 50 weeks in CNF group (p=0.02) and median time to progression was 51 and 33 weeks, respectively (p=0.0004). At the time of analysis, all except six patients (one in CNF and five in CEF) had died and the median survival time in the CEF group was longer than in CNF (74.4 weeks vs 51.4 weeks; log-rank 2 test p=0.015). CNF produced more hematologic toxicity than CEF (WHO scale; grades 2–4): leucopenia 84% vs 68% (p=0.03) and trombocytopenia 17% vs 4.5% (p=0.01); CEF caused more grade 2 and 3 alopecia: 93% vs 70% (p=0.00 1).Conclusion: The combination CEF using this schedule and dosage in metastatic breast cancer is more effective with less toxicity than CNF, except for alopecia, and was associated with longer survival.Breast Cancer Research and Treatment 10/1999; 58(2):141-150. · 4.43 Impact Factor -
Article: The likelihood ratio test for goodness of fit with fuzzy experimental observations
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ABSTRACT: Experiments are considered in which the person responsible for observation cannot crisply perceive the outcomes, but where each observable event can be identified with a fuzzy subset of the sample space. It is explained that in such a situation, the likelihood ratio test can immediately be derived for goodness of fit to a completely specified hypothetical distribution regarding the `exact experiment' on the basis of fuzzy information. On the other hand, if the hypothetical distribution involves unknown parameters the extension of the likelihood ratio test usually becomes unmanageable, because of the unoperativeness of the trivial generalization of the maximum likelihood principle to fuzzy observations. This last generalization is suitably approximated by means of the minimum inaccuracy principle of point estimation (introduced in previous papers as an operative extension of the maximum likelihood one, on the basis of the inaccuracy measure defined by D.F. Kerridge in 1961) whose use for the likelihood-ratio test for goodness of fit with fuzzy data provides a manageable procedureIEEE Transactions on Systems Man and Cybernetics 08/1989; -
Article: The fuzzy decision problem: An approach to the point estimation problem with fuzzy information
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ABSTRACT: This paper is devoted to the extension of the Bayesian method for the point estimation, when the available information is ‘vague’.In the nonfuzzy case, the parametric estimation can be approached as a particularization in the statistical decision problem. This motivates us to accomplish the mentioned extension by looking at the parametric estimation in the fuzzy case as a special situation in the fuzzy decision problem (defined by Tanaka, Okuda and Asia).In this way, concepts in the fuzzy decision problem are first ‘expressed’ in the estimation terminology. Then, on the basis of these concepts, we shall introduce some notions and state some interesting results. Finally, several illustrative examples will be exposed.European Journal of Operational Research 02/1985; · 1.82 Impact Factor -
Article: The minimum inaccuracy estimates in χ2 tests for goodness of fit with fuzzy observations
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ABSTRACT: A relevant problem in Statistics relates to obtaining conclusions about the shape of the distribution of an experiment from which a sample is drawn. We will consider this problem when the available information from the experimental performance cannot be exactly perceived, but that rather it may be assimilated with fuzzy information (as defined by L.A. Zadeh, and H. Tanaka, T. Okuda and K. Asai).If the hypothetical distribution is completely specified, the extension of the chi-square goodness of fit test on the basis of some concepts in Fuzzy Sets Theory does not entail difficulties. Nevertheless, if the hypothetical distribution involves unknown parameters, the extension of the chi- square goodness of fit test requires the estimation of those parameters from the fuzzy data. The aim of the present paper is to prove that, under certain natural assumptions, the minimum inaccuracy principle of estimation from fuzzy observations (which we have suggested in a previous paper as an operative extension of the maximum likelihood principle) supplies a suitable method for the above requirement.Journal of Statistical Planning and Inference. -
Article: Power analysis of QTL detection in half-sib families using selective DNA pooling.
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ABSTRACT: Individual loci of economic importance (QTL) can be detected by comparing the inheritance of a trait and the inheritance of loci with alleles readily identifiable by laboratory methods (genetic markers). Data on allele segregation at the individual level are costly and alternatives have been proposed that make use of allele frequencies among progeny, rather than individual genotypes. Among the factors that may affect the power of the set up, the most important are those intrinsic to the QTL: the additive effect of the QTL, and its dominance, and distance between markers and QTL. Other factors are relative to the choice of animals and markers, such as the frequency of the QTL and marker alleles among dams and sires. Data collection may affect the detection power through the size of half-sib families, selection rate within families, and the technical error incurred when estimating genetic frequencies. We present results for a sensitivity analysis for QTL detection using pools of DNA from selected half-sibs. Simulations showed that conclusive detection may be achieved with families of at least 500 half-sibs if sires are chosen on the criteria that most of their marker alleles are either both missing, or one is fixed, among dams.Genetics Selection Evolution 33(3):231-47. · 2.88 Impact Factor -
Article: Combining inter- and intrapopulation information with the Weitzman approach to diversity conservation.
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ABSTRACT: This article introduces a new perspective on Weitzman's methodology for assessing the distribution of resources in genetic diversity conservation programs. Intrapopulation information is added to the procedure by diffusion process formulas to calculate genetic extinction probabilities, and therefore the marginal diversities and elasticities of diversity. The method was tested with a set of European cattle breeds from Spain and France and provided satisfactory results.Journal of Heredity 96(6):704-12. · 2.80 Impact Factor -
Article: Asymptotic variances of QTL estimators with selective DNA pooling.
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ABSTRACT: Investigation on QTL-marker linkage usually requires a great number of observed recombinations, inferred from combined analysis of phenotypes and genotypes. To avoid costly individual genotyping, inferences on QTL position and effects can instead make use of marker allele frequencies. DNA pooling of selected samples makes allele frequency estimation feasible for studies involving large sample sizes. Linkage studies in outbred populations have traditionally exploited half-sib family designs; within the animal production context, half-sibships provide large families that are highly suitable for DNA pooling. Estimators for QTL position and effect have been proposed that make use of information from flanking markers. We present formulas derived by the delta method for the asymptotic variance of these estimators.Journal of Heredity 94(2):175-9. · 2.80 Impact Factor
