Multi-level code comprehension model for large scale software, A

1996 Fall.Includes bibliographical references (pages 142-147).For the past 20 years researchers have studied how programmers understand code they did not write. Most of this research has concentrated on small-scale code understanding. We consider it necessary to design studies that observe programmers working on large-scale code in production environments. We describe the design and implementation of such a study which included 11 maintenance engineers working on various maintenance tasks. The objective is to build a theory based on observations of programmers working on real tasks. Results show that programmers understand code at different levels of abstraction. Expertise in the application domain, amount of prior experience with the code, and task can determine the types of actions taken during maintenance, the level of abstraction at which the programmer works, and the information needed to complete a maintenance task. A better grasp of how programmers understand large scale code and what is most efficient and effective can lead to better tools, better maintenance guidelines, and documentation

Designing Tailorable Technologies

This paper provides principles for designing tailorable technologies. Tailorable technologies are technologies that are modified by end users in the context of their use and are around us as desktop operating systems, web portals, and mobile telephones. While tailorable technologies provide end users with limitless ways to modify the technology, as designers and researchers we have little understanding of how tailorable technologies are initially designed to support that end-user modification. In this paper, we argue that tailorable technologies are a unique technology type in the same light as group support systems and emergent knowledge support systems. This unique technology type is becoming common and we are forced to reevaluate existing design theory, methods of analysis, and streams of literature. In this paper we present design principles of Gordon Pask, Christopher Alexander, Greg Gargarian, and Kim Madsen to strengthen inquiry into tailorable technologies. We then apply the principles to designing tailorable technologies in order for their design to become more coherent and tractable. We conclude that designers need to build reflective and active design environments and gradients of interactive capabilities in order for technology to be readily modified in the context of its use

Development of An Empirical Approach to Building Domain-Specific Knowledge Applied to High-End Computing

This dissertation presents an empirical approach for building and storing knowledge about software engineering through human-subject research. It is based on running empirical studies in stages, where previously held hypotheses are supported or refuted in different contexts, and new hypotheses are generated. The approach is both mixed-methods based and opportunistic, and focuses on identifying a diverse set of potential sources for running studies. The output produced is an experience base which contains a set of these hypotheses, the empirical evidence which generated them, and the implications for practitioners and researchers. This experience base is contained in a software system which can be navigated by stakeholders to trace the "chain of evidence" of hypotheses as they evolve over time and across studies. This approach has been applied to the domain of high-end computing, to build knowledge related to programmer productivity. The methods include controlled experiments and quasi-experiments, case studies, observational studies, interviews, surveys, and focus groups. The results of these studies have been stored in a proof-of-concept system that implements the experience base

Paths Explored, Paths Omitted, Paths Obscured: Decision Points & Selective Reporting in End-to-End Data Analysis

Drawing reliable inferences from data involves many, sometimes arbitrary, decisions across phases of data collection, wrangling, and modeling. As different choices can lead to diverging conclusions, understanding how researchers make analytic decisions is important for supporting robust and replicable analysis. In this study, we pore over nine published research studies and conduct semi-structured interviews with their authors. We observe that researchers often base their decisions on methodological or theoretical concerns, but subject to constraints arising from the data, expertise, or perceived interpretability. We confirm that researchers may experiment with choices in search of desirable results, but also identify other reasons why researchers explore alternatives yet omit findings. In concert with our interviews, we also contribute visualizations for communicating decision processes throughout an analysis. Based on our results, we identify design opportunities for strengthening end-to-end analysis, for instance via tracking and meta-analysis of multiple decision paths

Increases of opportunistic species in response to ecosystem change:The case of the Baltic Sea three-spined stickleback

Under rapid environmental change, opportunistic species may exhibit dramatic increases in response to the altered conditions, and can in turn have large impacts on the ecosystem. One such species is the three-spined stickleback (Gasterosteus aculeatus), which has shown substantial increases in several aquatic systems in recent decades. Here, we review the population development of the stickleback in the Baltic Sea, a large brackish water ecosystem subject to rapid environmental change. Current evidence points to predatory release being the central driver of the population increases observed in some areas, while both eutrophication and climate change have likely contributed to creating more favourable conditions for the stickleback. The increasing stickleback densities have had profound effects on coastal ecosystem function by impairing the recruitment of piscivorous fish and enhancing the effects of eutrophication through promoting the production of filamentous algae. The increase poses a challenge for both environmental management and fisheries, where a substantial interest from the pelagic fisheries fleet in exploiting the species calls for urgent attention. While significant knowledge gaps remain, we suggest that the case of the Baltic Sea stickleback increase provides generalisable lessons of value for understanding and managing other coastal ecosystems under rapid change

Assimilation of Tracking Technology in the Supply Chain

While tracking technology has become increasingly accessible, firms still struggle with deploying these technologies into the supply chain. Using the complementary perspectives of transaction cost and institutional theory, we develop an understanding of how supply network, product, and environmental characteristics jointly impact tracking technology assimilation. We empirically test our model on a global dataset of 535 supply chain executives and decision makers. The results suggest that assimilation is frequently initiated by an external stakeholder in a firm\u27s supply chain and that firms must develop strong collaborative ties with their partners in order to take full advantage of this technology

Book-tax conformity: empirical evidence from Germany

We use a unique matched tax return - financial statement data set to examine the magnitude and sources of book-tax differences in Germany. For the first time, the data set enables us to evaluate the extent to which financial and tax accounting differ in Germany in the most accurate manner. Despite the close link between financial and tax accounting in Germany, we find that corporate taxable income and income reported to shareholders diverge considerably. Regression results suggest that this reporting gap is largely attributable to legal differences between financial and tax accounting and we cannot provide evidence that tax aggressive reporting adds to it. However, further analyses show that firms actively engaged in corporate restructuring exhibit larger book-tax differences than other firms. We interpret this result as evidence of firms willing to give up the administrative advantages of a one-book accounting system in order to achieve desired tax or financial accounting result, if book-tax conformity is not required. Thus, the results not only provide insights into the relatively unexplored area of behavioral response to changes in the degree of book-tax conformity, but also add a new perspective to the discussion surrounding the implementation of the German Accounting Law Modernization Act (BilMoG) in 2010