The Model for Estimating the Siftware Development Cost in Tanzania

Abstract

The main purpose of the study was to develop the models to be used by software developers, universities and software companies to improve the cost estimation accuracy by 100%. Delivering a software which was under realistic budget and time still is a challenge in Tanzania. The estimators were over estimate or under estimate the cost. It caused the success or the failure of the software projects. The data collection methods used were Interview and questionnaire for both Qualitative and quantitative approach methods respectively. The methods of data analysis were Descriptive statistics for quantitative and content analysis for qualitative. The researcher concentrated in three objectives which were to (1) Investigate the existing cost estimation techniques for a software project, (2) find out the software development methodologies used in Tanzania and their influence on the project cost and (3) design a new model for the cost estimation in the software development. Software developers and project managers in software field in Tanzania were randomly selected at a certain sample size in quantitative but in qualitative purposive sampling technique was selected. The reason for using purposive sampling, was because the researcher expect to choose people who can deliver the data and those people had an experience in software industry. Why random, every individual had an independent chance to be selected in the study. Based on the research done, the researcher found that 75% of the respondents under estimated the cost in the past 12 month. And those respondents who did over estimated the cost in the past 12 months were 46.67%. There were various cost estimation techniques which were used by software developers. One of the Technique was expert judgement which was obtained based on the criteria or expertise in the specific area of knowledge, an industry or a particular discipline. This was the problem because companies were not getting a lot of tenders because the one who was requesting for the estimation thought that the other company were cheap and their software quality were low or there were expensive and they didn’t know what they were doing. The results showed that Expert judgement technique was the mostly used by many of the respondents which were 25% of them, followed by pricing to win 19%. Software development were hard due to sometimes requirements might change in between or the requirements collected were inadequate without a knowledge of it. And this was due to the lack of knowledge from the person who was collecting the requirement or the customer did not know what she/he wants.