Wednesday, May 22, 2019
Effectiveness of Software Quality Assurance in Offshore Development Enterprises in Sri Lanka
EFFECTIVENESS OF SOFTWARE QUALITY ASSURANCE IN OFFSHORE phylogenesis ENTERPRISES IN SRI LANKA Malinda Sirisena, Department of Computer Science & Engineering, University of Moratuwa. ABSTRACT The aim of the research described in this thesis is to evaluate the effectiveness of softwargon convergence tone of voice dominance approaches of Sri Lankan offshore parcel development organizations, and to propose a framework which could be used across all offshore softw ar development organizations. An empirical translate was conducted using draw outd framework from popular computer software program choice evaluation moldings.The research instrument employed was a dubiousnessnaire survey among thirty seven Sri Lankan registered offshore software development organizations. The square upings demonstrate a positive view of Effectiveness of Software flavour toast the stronger predictors of St efficiency, Installability, correctness, Testability and Changeability. The presend believ es recommendations indicate a hire for ofttimes violence on software lumber sanction for the Sri Lankan offshore software development organizations. Keywords Software Quality Assurance (SQA), Offshore Software Development, Quality Assurance Evaluation Models, Effectiveness of Quality Assurance. BACKGROUND INFORMATION Software Quality Assurance (QA) plays a major role in successful instruction execution and maintenance of a software project. In many organizations, QA has been simply traded-off to project speak to 1. The motivation of this research is to in high spiritslight the value of Software Quality Assurance against the economic cost. The IEEE commonplace ANSI/IEEE 730-2002 defines software fictitious character assurance as a planned and taxonomic pattern of all proceedings necessary to provide adequate faith that the software conforms to established technical requirements2.QA is not only holding a direct relationship of meeting customer satisfaction, but it has a v ery high impact on project schedules and cost. Failing to pay attention is often resulted in budget overruns and schedule delays 3. Software Quality Assurance has paid bet on in many industries much(prenominal) as telecommunication, health, travel, law, hospital, government and schools in many Ameri fucking organizations. A system of teaching hospitals conservatively estimates $17. 8 million rescue on an investment of $2. 5 million in tonicity management over a five- category time period. The University of Pennsylvania saved more than $60,000 a year from one project focused on reducing mailing cost. The U. S. Bureau of Labor Statistics reduced the time privationed to produce the monthly Consumer Price suggest (CPI), compiled by 650 the great unwashed in five departments, by 33 percent with no loss in accuracy. 4 Even in Sri Lankan software engineering companies, dumbfound been recognized QA as an important element. In 2005, Affno (www. affno. lk) has won the National Best Quality Software Gold Award for their ingathering eTender, which essential for Sri Lanka Telecom to automatize their tendering process 5. 2 THEORETICAL BASE OF THE STUDY 2. WHAT IS SOFTWARE QUALITY The IEEE standard ANSI/IEEE 730-2002 defines software fictional character assurance as a planned and systematic pattern of all actions necessary to provide adequate confidence that the software conforms to established technical requirements2. By going down the path of IEEE definition, there are 2 major camps when specify software persona6 1. Conformance to specification role defines in legal injury of the train which the return or service meets its written specifications. 2. see customer needs meeting customers explicit or implicit needs, irrespective of any measurable product or service features.Currently software select assurance is measured in two ways from technical perspective and from user perspective7. In the technical perspective of measuring software quality is gr ound on specifications. Developers measure quality and ensure specifications in foothold of errors in code through examen process and through early(a) mechanisms such as formal specifications, structured programming8. End-user perspective of software quality is measured through user experience to denote how well software meets user expectations. exploiter dissatisfactions do not necessarily be resulting from failure to meet specifications or coding errors. . 2 SOFTWARE QUALITY MANAGEMENT PHILOSOPHIES This section of the literature presents various philosophies of quality from view points of quality management gurus. These quality management philosophies could be a good alternative to formalized quality delineates which the research is going to based on. Quality management requires customer satisfaction, prefers prevention to inspection, and recognizes management responsibility for quality9. 2. 2. 1 DEMING AND FOURTEEN POINTS FOR MANAGEMENT Walter Edward Deming defines quality in monetary value of customer satisfaction10.Customer satisfaction is beyond conformance to specifications. According to Deming, the judge of quality should be the end user or the customer. Deming argues that management system should implement in a way that everyone in the organization to be responsible for quality of their output to the internal stakeholders. He introduced quartetteteen points for management for people to understand and implement necessary quality transformation10 1. make constancy of purpose for improvement of product and service Stay in business and provide jobs through innovation, research, constant improvement and maintenance. 2.Adopt the freshly philosophy For the new economic age, management needs to take leadership for change into a learning organization. 3. C console dependence on mass inspection Eliminate the need for mass inspection by building quality into the product. 4. End awarding business on price Aim at minimum total cost and move towards singl e suppliers. 5. Improve constantly and forever the system of production and service Improvement is not a one-time effort. Management is obligated to continually hold off for ways to reduce waste and improve quality. 6. Institute training Workers should be trained properly on their jobs. . Institute leadership Leading shall consist of assist people to do a better job and to learn by objective methods. 8. Drive out fear To assure better quality and productivity, people feel secure. 9. Break down barriers surrounded by departments Team work culture across departments. 10. Eliminate slogans, exhortations and numerical targets Let workers formulate their own slogans. Then they forget be committed to the contents. 11. Eliminate numerical quotas or work standards Quotas take into account only numbers, not quality or methods. They are usually a guarantee of inefficiency and high cost.A person, in order to hold a job, exit try to meet a quota at any cost, including doing damage to the c ompany. 12. Remove barriers to winning pride in workmanship People are eager to do a good job and distressed when they cannot. 13. Institute a vigorous computer programme of education Both management and the work force volition piddle to be educated in the new knowledge and understanding, including teamwork and statistical techniques. 14. Take action to accomplish the transformation It will require a special top management team with a plan of action to carry out the quality mission.A critical mass of people in the company must understand the 14 points. 2. 2. 2 JURAN AND THE IMPORTANCE OF TOP MANAGEMENT COMMITMENT TO QUALITY Joseph M Juran proposes two meanings to quality11 1. Quality consists of those product features which meet the need of customers and thereby provide product satisfaction. 2. Quality consists of freedom from deficiencies. In the handbook Juran propose quality as fitness for use rather than meeting customer needs he argues that it is not a feasible task to meet customer need. His view is much closer to the thought conformance to specifications.Juran proposes three fundamental managerial processes for the task of managing quality. The three elements of the Juran Trilogy are11 1. Quality planning A process that identifies the customers, their requirements, the product and service features that customers expect, and the processes that will deliver those products and services with the shed light on attributes and then facilitates the transfer of this knowledge to the producing arm of the organization. 2. Quality control A process in which the product is examined and evaluated against the original requirements verbalised by the customer. Problems detected are then corrected. . Quality improvement A process in which the sustaining mechanisms are put in place so that quality can be achieved on a continuous basis. This includes allocating resources, assigning people to pursue quality projects, training those involved in pursuing projects, and in frequent establishing a permanent structure to pursue quality and maintain the gains secured. 2. 2. 3 CROSBY AND STRIVING FOR ZERO DEFECTS Philip B Crosby is a conformance to specification adherer. Crosby summarizes his perspective on quality in fourteen steps that is built around four fundamental absolutes of quality management12 1.Quality is defined as conformance to requirements, not as morality or elegance 2. The system for causing quality is prevention, not appraisal. That is, the quality system for suppliers attempting to meet customers requirements is to do it right the first time. Crosby is a strong advocate of prevention, not inspection. In a Crosby oriented quality organization everyone has the responsibility for his or her own work. There is no one else to catch errors. 3. The performance standard must be Zero Defects, not thats close enough. Crosby has advocated the notion that zero errors can and should be a target. . The amount of quality is the cost of quality. be of imperfection, if corrected, have an immediate beneficial effect on bottom-line performance as well as on customer relations. 2. 2. 4 ISHIKAWA AND FISHBONE DIAGRAM Kaoru Ishikawa defines quality as meeting customer needs13. He further argues that no specific quality standard could ever define and following them does not meet the pass judgment quality levels. According to Ishikawa, quality is a very broad c oncept which goes beyond product, service, process, information quality, etc.He introduced quality circles through Fishbone diagrams. 2. 2. 5 FEIGENBAUM AND TOTAL QUALITY controller Armand Vallin Feigenbaum built his thought around total quality control14. Feigenbaum states that quality is a dynamic factor which must be defined in terms of customer experiences. He further states that quality should satisfy customers explicit and implicit needs14. 2. 3 SOFTWARE QUALITY MODELS Previous section focus on divergent view points of quality management gurus. These points will be h elpful in solving common quality management problems in Sri Lankan, offshore enterprises.Quality management philosophies presented in the previous section fiddle flexible and qualitative view of quality this section will present a rigid and quantitative15 quality structure, which will be a roadmap of identifying free lance variables for current adopt. 2. 3. 1 MCCALLS QUALITY MODEL Jim McCalls quality lesson is primarily aimed towards the system developers and development process, however he has tried to bridge the gap between users and developers by focusing on number of quality factors, considering both users and developers priorities16, 17.The quality model is organized around three quality characteristics16 compute 1 McCalls quality model organized around three types of quality characteristics McCalls model furthermore elaborated with a hierarchy of factors, criteria and metrics around the three types of major perspectives. opine 2 McCalls quality model Eleven factors on th e left-hand side of the model represent the external view of quality as viewed by end users. These eleven factors attribute to twenty three quality criteria, which describe the internal view of software. The evaluation is done by answering each quality criteria with yes and no.Finally the quality level is derived as a pct based on the responses received as yes. 2. 3. 2 BOEHMS QUALITY MODEL Barry W Boehms model has similarities to McCalls model. His qualitative approach of defining quality stems from three levels in the hierarchy, which ends with primitive characteristics18. These primitive characteristics on an individual basis contribute to the overall quality level. Figure 3 Boehms software quality characteristics tree19. Quality measurement is carried out through extent or degree to which the product or service achieves each characteristic19. 2. 3. 3 ISO 9126Among the ISO 9000 series of quality standards, ISO has released the ISO 9126 Software Product Evaluation20. Figure 4 The ISO 9126 quality model 20. ISO further proposes quality characteristics/guidelines to evaluate the above sixsome areas of importance. Figure 5 ISO 9126 quality attributes Each quality factor/ six areas of importance is represented by sub-factors as depicted in the above diagram. Details of each selected attribute will be discussed in the next chapter. 3 CONCEPTUAL FRAMEWORK This chapter elaborates how the conceptual framework for the study has been derived through the existing work identified in the literature review. . 1 EXISTING WORK Since the study is on evaluating software quality from software developing organizations view, it is necessary to drop down the quality attributes discovered in the literature, only to represent developer view of software quality. Therefore it has been decided to take the union of developer related quality attributes from all three popular models referred in the previous chapter. It is not an favourable task to differentiate developer oriented qual ity attributes from user oriented attributes as quality classifications are different from each model and some attributes are indispensable to their multiple definitions.For a consistent interpretation of the quality attributes, the definitions of attributes have been used according to Software Engineering Institutes (SEI) Software Technology Roadmap glossary23 and ISO 912624 definitions. 3. 1. 1 DEVELOPER ORIENTED ATTRIBUTES FROM MCCALLS MODEL McCalls model mainly goes hand in hand with external quality factors. undermentioned are the quality attributes extracted from McCall model, which are related to developer related quality based on SEI definitions. Selected Attribute Maintainability SEI Definition23 The ease with which a software system or component can be odified to correct faults, improve performance, or other attributes, or adapt to a changed environment. The degree to which a system or component facilitates the establishment of test criteria and the performance of tests to determine whether those criteria have been met. The ease with which a system or component can be modified for use in applications or environments other than those for which it was specifically chassised. The ease with which a system or component can be transferred from one hardware or software environment to another. The degree to which a software module or other work product can be used in more than one computing program or software system. The ability of two or more systems or components to exchange information and to use the information that has been exchanged. Testability Flexibility Portability Reusability Interoperability Table 1 Developer related quality attributes from McCalls model 3. 1. 2 ADDITIONAL ATTRIBUTES FROM BOEHMS MODEL Boehms model, which has put the utility perspective in terms of quality, is much similar to McCalls model.After evaluating definitions, following two attributes were added to the list. Selected Attribute Understandability Modifiability SEI Definition23 The degree to which the purpose of the system or component is clear to the evaluator. The degree to which a system or component facilitates the incorporation of changes, once the nature of the desired change has been determined. Table 2 Additional developer related quality attributes from Boehms model 3. 1. 3 ADDITIONAL ATTRIBUTES FROM ISO 9126 Following are sub-attributes taken from the ISO 9126 definitions.Selected Attribute Analyzability ISO Definition24 The capability of the software product to be diagnosed for deficiencies or causes of failures in the software, or for the separate to be modified to be identified. The capability of the software product to enable a qualify modification to be implemented. The capability of the software product to avoid unexpected effects from modifications of the software. The capability of the software product to be adapted for different contract environments without applying actions or means other than those provided for thi s purpose for the software considered. The capability of the software product to be installed in a specified environment. The capability of the software product to co-exist with other independent software in a common environment sharing common resources. Changeability Stability Adaptability Installability Co-existence replaceability The capability of the software product to be used in place of another specified software product for the homogeneous purpose in the same environment. Table 3 Additional developer related quality attributes from ISO 9126 model 3. 1. 4 FINAL ATTRIBUTE LISTAfter analyzing the above mentioned attribute lists and completing the preliminary studies, the list could filter down to the following for the current study. 1. Correctness 2. Testability 3. Changeability 4. Stability 5. Installability In the following sections, each of above attribute will be discussed in terms of their quality characteristics. 3. 1. 4. 1 CORRECTNESS SEI defines correctness as The d egree to which a system or component is free from faults in its specification, design, and implementation23. McCall attributes correctness through16 Traceability Completeness consentThrough traceability, it makes execu submit to know the relationships of each module or component and thereby high confidence states correctness. Completeness assures that there are no parts left in terms in executing a live of a system or a procedure thereby 100% completeness ratio guarantees correctness. Inconsistent systems or functions will lead to higher error probability therefore it is a part of correctness. Through the initial discussions with some key personnel, it was revealed that these characteristics are equally hard to collide with to achieve Correctness. . 1. 4. 2 TESTABILITY SEI defines testability as The degree to which a system or component facilitates the establishment of test criteria and the performance of tests to determine whether those criteria have been met23. Both McCall and Boehm have attributed testability to quality assurance on following characteristics16, 18 Simplicity Instrumentation Self-descriptiveness Modularity and structuredness Accountability Accessibility Communicativeness. Simplicity of applications will make easier in interrogatory comparatively to abstruse applications.Instrumentation makes workable to put probes in the system in order to deduce test information. Self-descriptive systems have inbuilt help or system documentation which will be sufficient to understand the system by going through. Modularity helps in isolating system tests which structuredness denotes consistent organization of the system. Accountability on system for which it is possible to measure the usage of the code19. Such measurements are typically covered by debugging tools, which exist specifically for programming languages. Accessibility of a system allows usage of its parts in a selective manner19.This allows in creating flexible test scenarios. Through communicativeness, systems make easier to understand inputs and output, which makes easier to compose test causas. 3. 1. 4. 3 CHANGEABILITY ISO defines changeability as The capability of the software product to enable a specified modification to be implemented24. Changeability is an attribute defined in ISO 9126 and lacks supporting characteristic definitions. However changeability could be achieved through Aiming simple solution rather than complicated systems as by nature simple applications are easier to change. Low bring together of individual modules of a system as lower interactions make easier to change individual components. Designing the systems change in mind from the beginning musical composition memory application evolution. 3. 1. 4. 4 STABILITY ISO defines stability as The capability of the software product to avoid unexpected effects from modifications of the software24. Therefore stability in this context does not denote the ability of the system to show stable behavior when used. However, if modification often results in unexpected behavior, there will be a high impact on stability.Stability is directly influenced by Changeability. Low changeability is likely to show low stability. This will depict the fact that, hard to change a low changeable system will lead to a greater risk of instability. 3. 1. 4. 5 INSTALLABILITY ISO defines Installability as The capability of the software product to be installed in a specified environment24. Installability requirements are generally specified in the form of an installation process. The target environment in this case will have to be known at the development time.Installability is measured as a percentage exercised of the total specified Installability requirements. In the Sri Lankan context, Installability is commonly referred as Deployability. 3. 1. 5 RELATIONSHIPS OF VARIABLES Having identified the variables and attributes, it had been decided to limit the study to following variables, after interviewing key quality assurance personnel in target organizations. Based on their arguments, on applicability to offshore organizations, the best suited variables have been selected for the study. Dependent varying Effectiveness of Software Quality Assurance Independent Variables . Correctness a. Completeness b. Consistency 2. Testability a. Simplicity b. Modularity c. Structuredness 3. Changeability a. Simplicity b. Coupling 4. Stability a. Changeability 5. Installability Having identified the variables, following relationships have been derived based on the reviewed literature in the previous section. Correctness Testability Effectiveness of Software Quality Assurance Changeability Stability Installability Independent Variables Figure 6 Schematic diagram for conceptual framework Dependent Variable 3. 2 HYPOTHESES FORMULATEDIn order to statistically test the derived conceptual framework, following hypotheses have been theorize. Since the study is targeted to test each in dependent variable separately, hypotheses also have been formulated independently to each independent variable. H01 there is no relationship between the Correctness of software developed and released to QA team), on the effectiveness of software quality assurance approach. HA1 the greater the Correctness of software developed and delivered to QA team, the higher the effectiveness of software quality assurance approach.H02 there is no relationship between the Testability of software developed and released to QA team, on the effectiveness of software quality assurance approach. HA2 the greater the Testability of software developed and delivered to QA team, the higher the effectiveness of software quality assurance approach. H03 there is no relationship between the Changeability of software developed and released to QA team, on the effectiveness of software quality assurance approach. HA3 the greater the Changeability of software developed and delivered to QA team, the higher the effec tiveness of software quality assurance approach.H04 there is no relationship between the Stability of software developed and released to QA team, on the effectiveness of software quality assurance approach. HA4 the greater the Stability of software developed and delivered to QA team, the higher the effectiveness of software quality assurance approach. H05 there is no relationship between the Installability of software developed and released to QA team, on the effectiveness of software quality assurance approach. HA5 the greater the Installability of software developed and delivered to QA team, the higher the effectiveness of software quality assurance approach. question DESIGN Research design will outline the roadmap of achieving the research objectives thorough the identified variables and theoretical framework. Details of study Purpose of the study Type of investigating Extent of researcher interface Minimal studying events as they normally occur and defining a framework Study s etting bar Measurement and measures Effectiveness of Software Quality Assurance in Emerging Offshore Development Enterprises in Sri Lanka Descriptive quality evaluation framework Hypothesis testing to validate the evaluation frameworkCorrelation study of correlations to effectiveness against evaluation factors no(prenominal)contrived study in real business environment Quality factors and their applicability through quality matrices and Likert scales info analysis 1. Classification of data 2. Goodness of data Unit of analysis Sampling design Time horizon Data collection method 3. Hypotheses testing Individuals based on job categories in Offshoring organizations Judgmental sampling of individual in the entire population of offshore enterprises Crosssectional Interviews, Questionnaires, Observations Figure 7 The research design 4. 1 TYPE AND NATURE OF THE STUDYThe study was an empirical study through analysis of responses to the questionnaires which was formulated through the concept ual framework. 4. 2 DATA COLLECTION METHODS Since the study is on offshore software development organizations, it has been decided to collect data from all registered companies in Software Exporters Association Sri Lanka and seven other offshore software development organizations in Sri Lanka. There were forty seven registered members as of first August, 2007. Questionnaires were distributed to the key quality assurance person or to the most senior quality assurance person in each organization. . 2. 1 QUESTIONNAIRE DESIGN A structured questionnaire was used to gather responses apart from the preliminary interviews. The questionnaire is divided in to four main sections. Section one has eleven questions, capturing organizational demographics of the responder. Section two has six questions, to capture responders personal demographics. Section three is the main section of the questionnaire which captures organizations software quality assurance, project specific demographics and respons es to test the conceptual framework. Section four is targeted to capture additional information for the conceptual framework. RESULTS OF DATA depth psychology Responses received had been categorized to qualitative data and quantitative data. Qualitative data had been used to understand the responders and company background. Quantitative responses, where the scale data is measured have been assigned scores as per following table for statistical analysis. Response Selected potently disagree Disagree Neutral Agree Strongly agree Score Assigned 1 2 3 4 5 Table 5 Rates given for questionnaire responses Each response was individually assessed to ensure data validity and integrity.Incomplete responses have been followed up with the responder with available contact information and have been able to complete in many instances. For the fair responses, score three was assigned in case the question is not applicable to the responders organization. Following summary shows the statistics of the questionnaire diffusion and responses received. Number of Organizations that Questionnaire had been sent 47 SEA registered companies + 7 other offshore companies Total Responses Received 39 Invalid / Unusable 2 Number of Valid Responses 37Table 6 Statistics of questionnaire distribution responses received 5. 1 PILOT STUDY To test the primary data a pilot study was run among fourteen Quality Assurance Engineers at an offshore software development organization, using a outline questionnaire. On the scale of reliability in order to treat results with credibility25 and the internal consistency of the draft questionnaire, was checked by using Cronbachs of import coefficient. The alpha coefficient should be above . 7 for the scale to be reliable26. The overall Cronbachs alpha coefficient was . 81, indeed the questionnaire was considered to have a good internal consistency and suitable for collecting the data for the main study. Details of Cronbachs alpha are discussed under synopsis of Reliability Section, below. 5. 2 PRELIMINARY ANALYSIS All thirty seven organizations selected as valid responses are exporting software. 89. 19% of the selected organizations are locally own while 10. 81% of organizations which are in Sri Lankan carrying into action are owned by foreign parties. 64. 86% of the target organizations are project based companies while 21. 2% of the organizations focus only on their own products. However 13. 51% of the organizations undertake client projects while they market their own products. 10 8 No. of Organizations 6 4 2 0 1. 00 2. 00 3. 00 4. 00 5. 00 6. 00 7. 00 8. 00 12. 00 14. 00 No. of years in Sri Lankan Operation Figure 8 Analysis of organizations against number of years in operation According to the above graph, most of the Sri Lankan offshore organizations under the current study have started their operation two years before. 75. 68% of the responders were males and the balance 24. 32% were females.The come age of responders was 30. 11 years. On an average, they posses one year of experience in their current position in the respective organizations. The following chart represents the education level of responders. 30 25 20 Count 15 10 5 0 Non IT Graduate IT/Comp. Science point Graduate Graduate Deploma MSc/MBA/Post Graduate Degree Other Education Level Figure 9 Education level of responders Majority of quality assurance heads in the target organizations posses randomness Technology or a Computer Science degree. 3. 03% Little Early 9. 09% On Time 24. 24% Too hold up 3. 64% Little Delayed Figure 10 Project completion against estimates Responders were asked to select a completed project/product when they responded to part 3 of the questionnaire. The above pie chart highlights the project/product completion time against the estimates of the selected projects by the responders. From the selected projects/products, majority have been completed with a little delay from the estimates. Mean and the variance are calcu lated for each question under each independent variable and the dependent variable through the assigned scores as per Table 5.Question No. Question Mean dissension Effectiveness of Software Quality Assurance 18 19 20 21 22 23 Software QA is a very important make up in our organization Without QA our products/services will not meet current level of customer satisfaction Our Software QA approach/practice helps us in winning new businesses Our organization has adequate number of QA Human Resources Our organization has invested enough in Software QA tools Our Software Development or any other Process has considered QA as a major practice 3. 622 4. 081 3. 811 3. 919 3. 514 3. 865 0. 686 0. 99 0. 658 0. 465 0. 812 0. 842 Correctness 30 31 32 33 34 35 36 If the systems or components we deliver meet specifications to 100%, we can say that its a high quality factor Systems or components we deliver, always met specifications Uniformity of functionality/operations/ soaring of the designed sy stem always contributed to high quality System maintained Uniformity of functionality/operations/navigation across individual functions If a function of a system, completes its execution without in between failures, we can say it is a high quality factor.Our systems do not fail in executing a function or procedure to its completion Our QA team measures our systems, whether they meet specifications or not 3. 703 3. 568 3. 703 3. 324 3. 243 3. 243 4. 108 0. 604 1. 141 0. 715 1. 003 0. 745 0. 634 0. 544Testability 37 If all functionality/operations/navigation of systems could be tested enough, then we can say it denotes high quality All the functionality/operations/navigation of our systems are properly being tested by our QA team Even the complex operations of our systems are represented by simple user interactions in order to make applications simple and user friendly Our applications are decomposed in to manageable modules in implementation in a practical manner Consistent organizat ion of modules/code are evident in our applications Our QA team measures or put furiousness on testability (Simplicity, Modularity, structuredness) of applications during the QA cycle 4. 595 0. 303 38 4. 514 0. 312 39 4. 297 0. 270 40 3. 946 0. 330 41 3. 838 0. 417 42 4. 432 0. 308 Changeability 43 If a product allows a specified modification to be implemented without much difficulty, then we can say it denotes a high quality factor Our systems do not need much effort to fit minor specification changes (i. e.Adding a new field to a form) at implementation or quality assurance stage Our systems maintain low interactions between individual modules, therefore it is easier to change individual components without affecting others Our QA team measures put much emphasis to test changeability and stability of systems during the QA cycle 4. 000 0. 111 45 3. 946 0. 164 46 3. 838 0. 251 48 3. 919 0. 299 Stability 44 If the systems avoid unexpected effects after modifications, it denotes a hi gh quality or its a high quality factor After the design changes done to one module, our systems have very few side effects to other modules Our QA team measures put much emphasis to test changeability and stability of systems during the QA cycle 3. 595 . 359 47 3. 703 0. 437 48 3. 919 0. 299 Installability 49 If the system could be installed in a specified environment without challenges, it denotes high quality or it can be considered as a high quality factor Our systems do not get challenged during the installation in the agreed/specified environment Our QA team measures Installability of systems they test 3. 568 0. 863 50 3. 162 3. 541 0. 862 1. 311 51 Table 7 Means and variances of questions Frequency distributions of responses to each of above questions have been presented in Appendix 2. 5. 3 SECONDARY RESULTS ANALYSIS Primary data is further analyzed to derive more meaningful results.For statistical analysis, the ratings gathered through individual questions were summed up to derive scores for individual independent variables. Variable = sum of marks for relevant questions I. e. Correctness = Q30 + Q31 + Q32 + Q33 + Q34 + Q35 + Q36 Sample Mean, where, n = sample size, and = scores Sample Variance, Standard Deviation, Following table illustrates the statistics of independent variables, which denotes the effectiveness of quality assurance. Standard Deviation 0. 569 0. 552 0. 422 0. 327 0. 445 0. 752 Variable Effectiveness of QA Correctness Testability Changeability Stability Installability Mean 3. 802 3. 556 4. 270 3. 926 3. 739 3. 423 Variance 0. 324 0. 305 0. 178 0. 107 0. 198 0. 566Table 8 primary statistics of independent variables and the dependent variable Following is the graphical illustration of above statistics. 4. 500 4. 000 3. 500 3. 000 2. 500 2. 000 1. 500 1. 000 0. 500 0. 000 Mean Variance Std. Div. Figure 11 Basic statistics of independent variables According to the above illustration, Testability contributes to QA effectiveness most while Changeability remains at the second position. Installability was rated as of least evidential to the QA Effectiveness in the subject domain. 5. 3. 1 ANALYSIS OF RELIABILITY OF DATA Cronbachs alpha measure is used to determine how well the target independent variables measure single, unidimensional QA Effectiveness latent construct.Cronbachs alpha can be written as a function of the number of test items AND the average inter-correlation among the items. N where, N = number of items and = inter-item correlation among items. Cronbachs Alpha Based on Cronbachs Standardized Alpha ( Items . 912 . 918 Table 9 Reliability statistics N of Items 28 Cronbachs alpha for all twenty eight questions is 0. 912, which denotes that the collected data is acceptable for the research. 5. 4 HYPOTHESES TESTING Analysis had been done to test each set of hypothesis to find out whether there are relationships defined through the hypotheses exist among independent variables and the dependent variable.The co rrelations between the factors hypothesized to effectiveness of quality assurance shown in the following table Set of Hypothesis/Independent Variable H1Correctness H2Testability H3Changeability H4Stability H5Installability ** Correlation is significant at the 0. 01 level (2-tailed). Pearson Correlation/ Effectiveness of QA . 678** . 589** . 559** . 728** . 613** Sig. (2-tailed) . 000 . 000 . 000 . 000 . 000 Table 11 Correlations between hypotheses for quality assurance Hypothesis H1 According to Hypothesis H01, Correctness which is influenced by Consistency and Completeness has a positive relationship to effectiveness of software quality assurance approach. Since this hypothesis is supported by the data analysis (Sig. value was . 000, p
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