Is there a place for qualitative studies when identifying effort predictors?

Abstract

Background: Effort estimation is the key for efficiently managing Web projects and achieving their success. In order to correctly estimate, it is necessary to have a broad knowledge of the factors that influence effort estimation in Web projects. Aim: In this research we aim to increase the understanding of Web effort estimation by using a set of factors identified in literature along with the knowledge from experts in effort estimation. Method: We have gathered data from two different sources: (a) our previous work, in which we applied Grounded Theory procedures to identify factors that influence Web effort estimation from the point of view of Web project estimation experts; and (b) a Systematic Literature Review (SLR) extension, in which we identified factors reported in research papers. We have used the qualitative results from these sources to make comparisons and draw conclusions on factors affecting Web effort estimation. Results: We identified a total of 90 factors that influence effort estimation in Web projects. From this set, 30 factors were identified only in the qualitative study with experts in effort estimation, not being present in the SLR extension. Conclusions: By integrating the factors found in both our qualitative study with effort estimation experts and the SLR extension, we managed to create a comprehensive list of factors influencing effort estimation. Also, this set can be a starting point in the proposal of effort estimation models. Finally, the results from our comparison can be considered an indication that it is necessary to increase the employment of qualitative research to capture evidences regarding the current state of practice in Software Engineering.