Jorma Sajaniemi’s research while affiliated with University of Eastern Finland and other places

To address the problem of errors in spreadsheets, we have investigated spreadsheet authors mental models in a hope of finding cognition-based principles for spreadsheet visualization and debugging tools. To this end, we have conducted three empirical studies. The first study explored the nature of mental models of spreadsheet authors during explaining and debugging tasks. It was found that several mental models about spreadsheets are activated in spreadsheet authors minds. Particularly, when explaining a spreadsheet, the real-world and domain mental models are prominent, and the spreadsheet model is suppressed; however, when locating and fixing an error, one must constantly switch back and forth between the domain model and the spreadsheet model, which requires frequent use of the mapping between problem domain concepts and their spreadsheet model counterparts. The second study examined the effects of replacing traditional spreadsheet formulas with problem domain narratives in the context of a debugging task. Domain narratives were found to be easy to learn and they helped participants to locate more errors in spreadsheets. Furthermore, domain narratives also increased the use of the domain mental model and appeared to improve the mapping between the domain and spreadsheet models. The third study investigated the effects of allowing spreadsheet authors to fix errors by editing domain narratives, thus relieving them from the use of traditional low-level cell references. This scenario was found to promote spreadsheet authors using even more of their domain mental model in a manner that completely overshadowed the use of their spreadsheet mental model. Thus, from a mental model perspective, it is possible to devise a new spreadsheet paradigm that uses domain narratives in place of traditional spreadsheet formulas, thus automatically presenting spreadsheet content so that it prompts spreadsheet authors to think in a manner that closely corresponds to their mental models of the application domain.

Earlier research on spreadsheet authors' mental models has shown that people possess several types of information about spreadsheets. Especially, when explaining a spreadsheet, the real-world and domain mental models are prominent and the spreadsheet model is suppressed, but when locating and fixing an error, one must constantly switch back and forth between the domain model and the spreadsheet model, which requires frequent use of the mapping between problem domain concepts and their spreadsheet model counterparts. This paper introduces a new spreadsheet visualization tool and its empirical evaluation. The tool translates traditional spreadsheet formulas into problem domain narratives and highlights referenced cells. The tool was found to be easy to learn and helped the participants to locate more errors in spreadsheets. Furthermore, the tool increased the use of the domain mental model and appeared to improve the mapping between the spreadsheet model and the domain model.

Earlier research on spreadsheet authors' mental models has shown that people possess several types of information about spreadsheets. The research results also suggested that a tool intended to aid in comprehension and debugging of spreadsheets should make prominent real-world and problem domain concepts and map them easily to spreadsheet-specific details. This poster introduces a new spreadsheet visualization tool which was developed to demonstrate that it is possible to have an easy-to-use spreadsheet understanding and debugging tool that relieves users from spreadsheet details and lets them utilize more of their mental model of the application domain. The tool translates traditional spreadsheet formulas into problem domain narratives and highlights referenced cells.

In this paper, we report on an empirical study exploring the nature of mental models of spreadsheet authors when they are explaining and debugging their own spreadsheets. Study participants were first asked to explain one of their own spreadsheets, and then to find and fix seeded errors in the same spreadsheets. Talk-aloud protocols were collected and analyzed to reveal the nature of participants' mental models in these activities. The findings indicate that the authors explain their spreadsheets mainly in terms of real-world and problem domain concepts; in debugging, they constantly switch between problem domain concepts and spreadsheet-specific concepts, although they mainly use spreadsheet-specific concepts to fix an identified error. These study findings provide insights on the need for developing spreadsheet authoring and debugging tools that correspond to spreadsheet authors' mental models of spreadsheets.

In computer science education and research into the psychology of programming, program summary analysis has been used to characterize mental models of novice and expert programmers and to measure learning outcome of programs and programming concepts. This paper reports an investigation where three raters used Good's program summary analysis scheme consisting of two independent classifications of program summary segments: information types and object description categories. The problems in using the scheme as well as differences between the raters were recorded and analyzed. The findings indicate that by improving the scheme and its documentation, most of the observed inter-rater differences can be avoided. The only open problem concerns making the distinction between descriptions of data and activities in cases where the specific words that are used, or the abstractness of expression may affect raters' interpretation of the information type.

Testing in companies with highly competitive environments has many opportunities and challenges. Testing is diversified, both contextually and geographically: there are many testing goals, many ongoing parallel projects, many testing phases and all this needs to be managed so that the full view of testing is visible for management and reporting. Testing is also linked to project communication and psychology: communication needs to be constructive, and testers and test leaders should have good interpersonal skills. It really does matter how a failure or test report is formulated. In order to localize testing problems in a large software-intensive company, we conducted a current state analysis via web-based questionnaire among experienced testing practitioners, most having at least 5 years experience in these tasks. The scope of the survey was decided to keep broad with the goal of finding future improvements within tool, process and method development. In this paper, we will concentrate on those survey results that have psychological underlying. Based on the results, we suggest a set of improvements for testing and, especially, test reporting. Implementation of these improvements is still underway, but the findings and suggestions provide insight into psychology of testing.

When visualization tools utilized in computer programming education have been evaluated empirically, the results have remained controversial. To address this problem, we have developed a model of short-term effects of program animation, and used it in a series of experiments. In the current experiment, we varied visual representation of an animation tool and the type of students' engagement. Results of the current experiment analyzed together with the results from the earlier experiments provided support for the hypothesis that what a student does plays a more central role in the usefulness of a visualization than representation used by the tool. Moreover, the levels of engagement as they are generally used in the research literature seem not to be the best possible indicators of the effectiveness of a visualization. (Contains 11 tables and 4 figures.)

A smoothly running software production line (SPL) requires consistent family-viewpoint awareness among the stakeholders through the development cycle, which in software-intensive products' engineering extends from requirements elicitation and marketing to detailed design and integration testing. To improve knowledge sharing among the stakeholders, we developed a documentation model based on feature modelling, and implemented it in a concurrent and multi-site development environment In this paper we share our experience from the field, gathered during the development and qualitative and quantitative performance analysis of this production-line kind of software development environment.

Programming education has experienced a shift from imperative and procedural programming to object-orientation. This shift has been motivated by educators' desire to please the information technology industry and potential students; it is not motivated by research either in psychology of programming or in computer science education. There are practically no results that would indicate that such a shift is desirable, needed in the first place, or even effective for learning programming. Moreover, there has been an implicit assumption that classic results on imperative and procedural programming education and learning apply to object-oriented programming (OOP) as well. We argue that this is not the case and call for systematic research into the fundamental cognitive and educational issues in learning and teaching OOP. We also present a research agenda intended to improve the understanding of OOP and OOP education.