Fj Fred Heemstra

Software cost estimation

The paper gives an overview of the state of the art of software cost estimation (SCE). The main questions to be answered in the paper are: (1) What are the reasons for overruns of budgets and planned durations? (2) What are the prerequisites for estimating? (3) How can software development effort be estimated? (4) What can software project management expect from SCE models, how accurate are estimations which are made using these kind of models, and what are the pros and cons of cost estimation models?

Are software cost-estimation models accurate

Abstract The use of a model is one way to estimate a software development project. The paper describes an experiment in which a number of automated versions of estimating models were tested. During the experiment, experienced project leaders were asked to make a number of estimates for a project. This related to a project that had actually been carried out. On the basis of the differences found between the estimates and reality, it is concluded that no proof is given that the models can be used for estimating projects at an early stage of system development. Therefore, only limited confidence should be placed in estimates that are obtained with a model only.

Sizing ERP implementation projects: an activity-based approach

ERP implementation projects affect large parts of an implementing organization and lead to changes in the way an organization performs its tasks. The costs needed for the effort to implement these systems are hard to estimate. Research indicates that the size of an ERP project can be a useful measurement for predicting the effort required to complete an ERP implementation project. However, such a metric does not yet exist. Therefore research should be carried out to find a set of variables which can define the size of an ERP project. This paper describes a first step in such a project. It shows 21 logical clusters of ERP implementation project activities based on 405 ERP implementation project activities retrieved from literature. Logical clusters of ERP project activities can be used in further research to find variables for defining the size of an ERP project.

Software cost estimation models

The importance of accurate cost estimates is discussed, and an overview of the existing methods for cost estimation is given. One class of models, namely, the parametric models, is then considered. The principles of parametric cost estimation models are examined, and an overview of such model is given. The existing models are compared, focusing mainly on the question of how accurate their estimates are. The advantages of the parametric models are described, and the state of the art is evaluated.<<ETX>>