Investigating Automatic Static Analysis Results to Identify Quality Problems: an Inductive Study

Background: Automatic static analysis (ASA) tools examine source code to discover "issues", i.e. code patterns that are symptoms of bad programming practices and that can lead to defective behavior. Studies in the literature have shown that these tools find defects earlier than other verification activities, but they produce a substantial number of false positive warnings. For this reason, an alternative approach is to use the set of ASA issues to identify defect prone files and components rather than focusing on the individual issues. Aim: We conducted an exploratory study to investigate whether ASA issues can be used as early indicators of faulty files and components and, for the first time, whether they point to a decay of specific software quality attributes, such as maintainability or functionality. Our aim is to understand the critical parameters and feasibility of such an approach to feed into future research on more specific quality and defect prediction models. Method: We analyzed an industrial C# web application using the Resharper ASA tool and explored if significant correlations exist in such a data set. Results: We found promising results when predicting defect-prone files. A set of specific Resharper categories are better indicators of faulty files than common software metrics or the collection of issues of all issue categories, and these categories correlate to different software quality attributes. Conclusions: Our advice for future research is to perform analysis on file rather component level and to evaluate the generalizability of categories. We also recommend using larger datasets as we learned that data sparseness can lead to challenges in the proposed analysis proces

A Case Study on Effectively Identifying Technical Debt

Context: The technical debt (TD) concept describes a tradeoff between short-term and long-term goals in software development. While it is highly useful as a metaphor, it has utility beyond the facilitation of discussion, to inspire a useful set of methods and tools that support the identification, measurement, monitoring, management, and payment of TD. Objective: This study focuses on the identification of TD. We evaluate human elicitation of TD and compare it to automated identification. Method: We asked a development team to identify TD items in artifacts from a software project on which they were working. We provided the participants with a TD template and a short questionnaire. In addition, we also collected the output of three tools to automatically identify TD and compared it to the results of human elicitation. Results: There is little overlap between the TD reported by different developers, so aggregation, rather than consensus, is an appropriate way to combine TD reported by multiple developers. The tools used are especially useful for identifying defect debt but cannot help in identifying many other types of debt, so involving humans in the identification process is necessary. Conclusion: We have conducted a case study that focuses on the practical identification of TD, one area that could be facilitated by tools and techniques. It contributes to the TD landscape, which depicts an understanding of relationships between different types of debt and how they are best discovered

Investigating Technical Debt Folklore - Shedding some light on technical debt opinion

We identified and organized a number of statements about technical debt (TD Folklore list) expressed by practitioners in online websites, blogs and published papers. We chose 14 statements and we evaluated them through two surveys (37 practitioners answered the questionnaires), ranking them by agreement and consensus. The statements most agreed with show that TD is an important factor in software project management and not simply another term for “bad code”. This study will help the research community in identifying folklore that can be translated into research questions to be investigated, thus targeting attempts to provide a scientific basis for TD management

Investigating Technical Debt Folklore - Shedding some light on technical debt opinion

We identified and organized a number of statements about technical debt (TD Folklore list) expressed by practitioners in online websites, blogs and published papers. We chose 14 statements and we evaluated them through two surveys (37 practitioners answered the questionnaires), ranking them by agreement and consensus. The statements most agreed with show that TD is an important factor in software project management and not simply another term for "bad code". This study will help the research community in identifying folklore that can be translated into research questions to be investigated, thus targeting attempts to provide a scientific basis for TD management

Comparing Four Approaches for Technical Debt Identification

Background: Software systems accumulate technical debt (TD) when short-term goals in software development are traded for long term goals (e.g., quick-and-dirty implementation to reach a release date vs. a well-refactored implementation that supports the long term health of the project). Some forms of TD accumulate over time in the form of source code that is difficult to work with and exhibits a variety of anomalies. A number of source code analysis techniques and tools have been proposed to potentially identify the code-level debt accumulated in a system. What has not yet been studied is if using multiple tools to detect TD can lead to benefits, i.e. if different tools will flag the same or different source code components. Further, these techniques also lack investigation into the symptoms of TD “interest” that they lead to. To address this latter question, we also investigated whether TD, as identified by the source code analysis techniques, correlates with interest payments in the form of increased defect- and change-proneness. Aims: Comparing the results of different TD identification approaches to understand their commonalities and differences and to evaluate their relationship to indicators of future TD “interest”. Method: We selected four different TD identification techniques (code smells, automatic static analysis (ASA) issues, grime buildup, and modularity violations) and applied them to 13 versions of the Apache Hadoop open source software project. We collected and aggregated statistical measures to investigate whether the different techniques identified TD indicators in the same or different classes and whether those classes in turn exhibited high interest (in the form of a large number of defects and higher change proneness). Results: The outputs of the four approaches have very little overlap and are therefore pointing to different problems in the source code. Dispersed coupling and modularity violations were co-located in classes with higher defect proneness. We also observed a strong relationship between modularity violations and change proneness. Conclusions: Our main contribution is an initial overview of the TD landscape, showing that different TD techniques are loosely coupled and therefore indicate problems in different locations of the source code. Moreover, our proxy interest indicators (change- and defect-proneness) correlate with only a small subset of TD indicators

Predictors of ceasing or reducing statin medication following a large increase in the consumer co-payment for medications: A retrospective observation study

Objectives: Previous Australian research has shown that following the 21% increase in the patient co-payments in 2005, the use of lipid-lowering therapy declined by 5%. This study aimed to determine the demographic and clinical characteristics of individuals who continued, reduced or ceased their use of statin medication in 2005. Study type: Retrospective observational study using routinely collected administrative data. Method: Pharmaceutical claims, hospital separations, and mortality records from 2000–2005 were used from the Western Australian (WA) population. The cohort comprised stable users of statin medication in 2004. We identified individuals who i) continued using statins, ii) reduced their use by ≥20%, or iii) ceased therapy for at least the first six months in 2005, based on changes in statin use between 2004 and 2005. Multivariate logistic regression models were used to determine whether the demographic and clinical characteristics of the three groups differed. Results: There were 205 924 statin users identified in Australia in 2004. After the January 2005 Pharmaceutical Benefits Scheme (PBS) co-payment increase, 3.2% of individuals ceased their regular statin therapy, 12.9% reduced statin use and 83.9% continued statin usage. This was an increase of 2.1% in statin users reducing or ceasing therapy compared to 2004. Predictors of cessation and reduction of statin therapy included younger age, greater socio-economic disadvantage, residing in very remote areas, having general beneficiary status, being a new statin user, having no prior history of ischaemic heart disease, having no prior history of a coronary artery revascularisation procedure, taking no other cardiovascular medication or diabetic medication, taking an increased number of medications and having a lower adherence level to statin medication in 2004. Conclusion: Compared to 2004, an additional 2.1% of statin users reduced or discontinued medication use in 2005, which may be attributed to an increase in the medication co-payment. Individuals with general beneficiary status, younger and healthier people were at particular risk of cessation or reduction in statin use in 2005

Rodents as receptor species at a tritium

New methods are being employed on the Department of Energy’s Savannah River Site to deal with the disposal of tritium, including the irrigation of a hardwood/pine forest with tritiated water from an intercepted contaminant plume to reduce concentrations of tritium outcropping into Fourmile Branch, a tributary of the Savannah River. The use of this system has proven to be an effective means of tritium disposal. To evaluate the impact of this activity on terrestrial biota, rodent species were captured on the tritium disposal site and a control site during two trapping seasons in order to assess tritium exposure resulting from the forest irrigation. Control site mice had background levels of tritium, 0.02 Bq/mL, with disposal site mice having significantly higher tritium concentrations, meanZ34.86 Bq/mL. Whole body tritium concentrations of the mice captured at the disposal site were positively correlated with tritium application and negatively correlated with precipitation at the site

Impact of consumer copayments for subsidised medicines on health services use and outcomes: A protocol using linked administrative data from Western Australia

Introduction: Across the world, health systems are adopting approaches to manage rising healthcare costs. One common strategy is a medication copayments scheme where consumers make a contribution (copayment) towards the cost of their dispensed medicines, with remaining costs subsidised by the health insurance service, which in Australia is the Federal Government. In Australia, copayments have tended to increase in proportion to inflation, but in January 2005, the copayment increased substantially more than inflation. Results from aggregated dispensing data showed that this increase led to a significant decrease in the use of several medicines. The aim of this study is to determine the demographic and clinical characteristics of individuals ceasing or reducing statin medication use following the January 2005 Pharmaceutical Benefit Scheme (PBS) copayment increase and the effects on their health outcomes. Methods and analysis: This whole-of-population study comprises a series of retrospective, observational investigations using linked administrative health data on a cohort of West Australians (WA) who had at least one statin dispensed between 1 May 2002 and 30 June 2010. Individual-level data on the use of pharmaceuticals, general practitioner (GP) visits, hospitalisations and death are used. This study will identify patients who were stable users of statin medication in 2004 with follow-up commencing from 2005 onwards. Subgroups determined by change in adherence levels of statin medication from 2004 to 2005 will be classified as continuation, reduction or cessation of statin therapy and explored for differences in health outcomes and health service utilisation after the 2005 copayment change

Bioprocessing in Microgravity: Applications of Continuous Flow Electrophoresis to Rat Anterior Pituitary Particles

In this report we describe the results of a continuous flow electrophoresis (CFE) experiment done on STS-65 in which we tested the idea that intracellular growth hormone (GH) particles contained in a cell lysate prepared from cultured rat anterior pituitary cells in microgravity might have different electrophoretic mobilities from those in a synchronous ground control cell lysate. Collectively, the results suggested that CFE processing in microgravity was better than on earth; more samples could be processed at a time (6 x) and more variant forms of GH molecules could be resolved as well. We had also hoped to carry out a pituitary cell CFE experiment, but failure of the hardware required that the actual cell electrophoresis trials be done on earth shortly after Shuttle landing. Data from these experiments showed that space-flown cells possessed a higher electrophoretic mobility than ground control cells, thereby offering evidence for the idea that exposure of cultured cells to microgravity can change their net surface charge-density especially when the cells are fed. Collectively, the results from this pituitary cell experiment document the advantage of using coupled cell culture and CFE techniques in the microgravity environment

Empirical Investigation on Agile Methods Usage: Issues Identified from Early Adopters in Malaysia

Agile Methods are a set of software practices that can help to produce products faster and at the same time deliver what customers want. Despite the benefits that Agile methods can deliver, however, we found few studies from the Southeast Asia region, particularly Malaysia. As a result, less empirical evidence can be obtained in the country making its implementation harder. To use a new method, experience from other practitioners is critical, which describes what is important, what is possible and what is not possible concerning Agile. We conducted a qualitative study to understand the issues faced by early adopters in Malaysia where Agile methods are still relatively new. The initial study involves 13 participants including project managers, CEOs, founders and software developers from seven organisations. Our study has shown that social and human aspects are important when using Agile methods. While technical aspects have always been considered to exist in software development, we found these factors to be less important when using Agile methods. The results obtained can serve as guidelines to practitioners in the country and the neighbouring regions