Example solutions: ETSF01 Software Engineering Process - Economy and Quality

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1 Example solutions: ETSF01 Software Engineering Process - Economy and Quality Introduction This document shows example of solutions to the problems in the document Exempel på tentafrågor. Please note that this is just ONE solution, there could be other solutions that are correct as well. Problems Effort Estimations (P1) Ge konkreta exempel på en Parametric Model, en analogiteknik, och en expert judgment kostnadsskattningsteknik, beskriv hur de används samt när respektive stil passar bra och/eller dåligt. Example of a solution for analogy based effort estimation technique: One concrete example of an analogy based effort estimation technique is: Case-Based Reasoning. Case-Based Reasoning identifies completed projects with similar characteristics to the new project. The effort of the matching case is then used as a base estimate for the new project. Then, the differences between the old projects and the new project are identified and the base estimate is adjusted to produce an effort estimate for the new project. A similarity function is used to identify matching cases and to retrieve the most similar past cases, while an adaption rule is used to adapt the solutions of the past projects. Case-Based Reasoning is applicable when other projects in the same application domain have been done in the past, i.e. there is a database with historical projects and characteristics. An advantage of Case-Based Reasoning is that it provides accurate estimates if similar project data are available. Disadvantages of Case-Based Reasoning: impossible to use if no comparable projects are available, the database with past projects needs to be systematically maintained, and it is not clear how to define a good similarity function. Please note that this is only a solution for an analogy based effort estimation technique. To fully answer this question you must provide a similar description for a parametric model (e.g. COCOMO II) and for one expert judgment technique (e.g. planning poker). The Role of Project Manager (P2) Det är inte ovanligt att en person går från att vara utvecklare till projektledare. Jämför vilka kompetenser och uppgifter som är viktiga i de båda rollerna, samt vilka ansvar som tillkommer och upphör med den nya rollen. Important skills for a software developer include the ability to solve problems, working in teams, and having knowledge about different programming languages. Important tasks for a software developer are coding, testing (e.g. unit testing),

2 breaking down higher-level requirements into detailed requirements, interpret and follow technical plans, and perform effort estimations of detailed requirements. A software project manager also needs to be able to solve problems, i.e. to come up with solutions when problems emerge. However, the problems to be solved are different. For example, while a developer may solve a problem of how to implement a requirement or how to optimize the code, the project manager may have to come up with a solution of how to reallocate the resources to be able to deliver on time. Both roles include the task of performing effort estimations. While a developer may only estimate the effort of detailed requirements, a software project manager may also need to perform effort estimations earlier in the project lifecycle, e.g. during the project planning step analyze project characteristic. A software project manager needs to perform other tasks that are not required by a software developer, to conduct a feasibility study, i.e. is it worth doing a certain project, and planning the project, i.e. how should the project be carried out. Planning the project includes activities such as performing a risk assessment, and in some cases calculates a detailed cost schedule over the project life of the project. Hence, a software project manager needs skills in budgeting. Moreover, a software project manager has the task of selecting the right people for the job, monitoring the performance of the project and report it to top-management. Although a software developer needs to report his/her progress to the project manager, the developer does not monitor the progress of the either project. Resource Allocation (P3) Lyckade projektscheman (project scheduling) är inte en enkel sekvens. Förklara hur aktiviteterna i bilden hänger ihop, hur dom påverkar varandra, och vilka konsekvenser som ev. kan uppstå om någon utelämnas och/eller hanteras på ett inkorrektsätt. The activity plan is used to plan the coming activities in the project, to see the dependencies between activities, when each activity should start and when they are

planned to be finished. This information is then used as a basis for the risk assessment. The risk assessment and activity plan provides input to resource allocation.

3 planned to be finished. This information is then used as a basis for the risk assessment. The risk assessment and activity plan provides input to resource allocation. The allocated resources and the activity plan are used to calculate a detailed cost schedule over the life of the project. The cost schedule provides a more accurate estimate of costs and serves as a plan against which project progress can be monitored. In practice, successful resource allocation may require a revision of the activity plan, e.g. if needed resources exceeds available resources, which in turn also affects the risk assessment. The cost schedule may indicate a need to reallocate resources or revise the activity plan, e.g. if the cost schedule indicates a higher overall project cost than originally anticipated. If projects activities are not properly planned, important risks may not be identified, less resources than needed may be allocated to the project, and the cost schedule may exceed the anticipated cost for the project. Task Scheduling (P4) Antag att ni skall göra en detaljerad plan för ett projekt. Antag att ni har identifierat 6 aktiviteter (a, b, c, d, e, f) för det här projektet. Estimerad tid (estimated duration) och beroenden (dependent on task) för varje aktivitet finns i tabellen nedan. Activity Estimated Duration [weeks] Dependent on Task(s) a 6 b 4 c 3 a d 4 b e 6 b f 2 c, d Rita ett aktivitetsdiagram (activity network) för projektet som inkluderar earliest start date, the latest start date, the earliest end date, the latest end date, and the float. Finns det någon critical path, och i så fall vilken är den? Solution: ????? F ????? Critical path is: A-C-F

4 Software Quality and Software Process Improvement (P5) Diskutera (resonera) hur software quality är relaterat till software process improvement. It is generally accepted that the quality of a product is largely determined by the quality of the process that is used to develop and maintain it. However, whether the practices in Software Process Improvement (SPI) frameworks lead to higher quality software may be argued. To address such concerns and specifically to identify if SPI frameworks may lead to higher software quality, we can map the Specific Goals and Practices of CMMI to software quality aspects. For example, CMMI has a specific goal about performing peer reviews. The purpose of peer reviews is to remove defects from the software products early and efficiently. Hence, if fewer bugs are found in the released software, the quality could be seen as higher. Moreover, another specific goal in CMMI is to manage requirements, which includes obtaining an understanding of the requirements. If the requirements engineering process is improved and leads to a better understanding of what the customers want and need, the quality of the software can be seen as higher by the customer. If a bottom-up SPI framework is used, e.g. the improvement framework utilizing light weight assessment and improvement planning (iflap), where the assessment is performed by eliciting improvements issues based on the organization s experience and knowledge, one improvement suggestion may be to improve the testing process to cover more test cases, which may find more bugs that could be corrected before the software product is released. Thus, the product has a higher quality. However, even if the processes are improved and are seen to be of high quality, people are conducting peer reviews and may not be able to find all bugs in the software, people are eliciting requirements from their customers and may not understand their customers fully, which may lead to an improved overall quality of the software product. Software Project Management (P6) Många tekniker i generell projekthantering (project management) kan också användas i software project management. Varför behövs software project management, dvs. vad skiljer generella projekt mot mjukvaruprojekt? Software projects are not very different from other engineering projects; many techniques in general project management can be applied to software project management. However, some characteristics have been identified that makes software projects more difficult. Software projects are invisible, i.e. the progress is not immediately visible, which is the case for, e.g. when a bridge is constructed. Software projects are more complex than any other engineering artifact. Other engineering disciplines often works with physical systems, e.g. cement. Although the physical systems have complexity, consistent physical laws govern them. Software developers must conform to requirements of humans, which can be inconsistent. Software is easy to change, which

5 is considered as a strength. However, when a software system interfaces with a physical system, it is expected that the software will change to accommodate the physical components. Therefore, software systems are particular subject to change.

7.5 ECTS. Materialplanering och Styrning. Ladokcode: The exam is given to: 41I29M, A900TI TGIAF15h, TGIAL15h, TGILO15h, International Students

7.5 ECTS. Materialplanering och Styrning. Ladokcode: The exam is given to: 41I29M, A900TI TGIAF15h, TGIAL15h, TGILO15h, International Students Materialplanering och Styrning 7.5 ECTS Ladokcode: The exam is given to: 41I29M, A900TI TGIAF15h, TGIAL15h, TGILO15h, International Students ExamCode: Date of exam: 2018-01-08 Time: 14:00 18:00 Means of