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A project effort estimation study

Ohlsson, Magnus C.; Wohlin, Claes LU and Regnell, Björn LU (1998) In Information and Software Technology 40(14). p.831-839
Abstract
This paper outlines a four step effort estimation study and focuses on the first and second step. The four steps are formulated to successively introduce a more formal effort experience base. The objective of the study is to evaluate the needed formalism to improve effort estimation and to study different approaches to record and reuse experiences from effort planning in software projects. In the first step (including seven projects), the objective is to compare estimation of effort based on a rough figure (indicating approximate size of the projects) with an informal experience base. The objective of the second step is on reuse of experiences from an effort experience base, where the outcomes of seven previous projects were stored. Seven... (More)
This paper outlines a four step effort estimation study and focuses on the first and second step. The four steps are formulated to successively introduce a more formal effort experience base. The objective of the study is to evaluate the needed formalism to improve effort estimation and to study different approaches to record and reuse experiences from effort planning in software projects. In the first step (including seven projects), the objective is to compare estimation of effort based on a rough figure (indicating approximate size of the projects) with an informal experience base. The objective of the second step is on reuse of experiences from an effort experience base, where the outcomes of seven previous projects were stored. Seven new projects are planned based on the previous experiences. The plans are, after project completion, compared with the initial plans and with the data from six out of the seven new projects, to plan the seventh. It is clear from the studies that effort estimation is difficult and that the mean estimation error is in the range of 14%-19% independent of the approach used. Further, it is concluded that the best estimates are obtained when the projects use the previous experience and complement this information with their own thoughts and opinions. Finally, it is concluded that data collection is not enough in itself, the data collected must be processed, i.e. interpreted, generalized and synthesized into a reusable form. (Less)
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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Information and Software Technology
volume
40
issue
14
pages
831 - 839
publisher
Elsevier
external identifiers
  • scopus:0032302278
ISSN
0950-5849
DOI
10.1016/S0950-5849(98)00097-4
language
English
LU publication?
yes
id
ec8ef342-c49b-49c7-a6ef-c22771a8a3b2 (old id 777974)
date added to LUP
2007-12-19 16:26:33
date last changed
2017-01-01 07:05:37
@article{ec8ef342-c49b-49c7-a6ef-c22771a8a3b2,
  abstract     = {This paper outlines a four step effort estimation study and focuses on the first and second step. The four steps are formulated to successively introduce a more formal effort experience base. The objective of the study is to evaluate the needed formalism to improve effort estimation and to study different approaches to record and reuse experiences from effort planning in software projects. In the first step (including seven projects), the objective is to compare estimation of effort based on a rough figure (indicating approximate size of the projects) with an informal experience base. The objective of the second step is on reuse of experiences from an effort experience base, where the outcomes of seven previous projects were stored. Seven new projects are planned based on the previous experiences. The plans are, after project completion, compared with the initial plans and with the data from six out of the seven new projects, to plan the seventh. It is clear from the studies that effort estimation is difficult and that the mean estimation error is in the range of 14%-19% independent of the approach used. Further, it is concluded that the best estimates are obtained when the projects use the previous experience and complement this information with their own thoughts and opinions. Finally, it is concluded that data collection is not enough in itself, the data collected must be processed, i.e. interpreted, generalized and synthesized into a reusable form.},
  author       = {Ohlsson, Magnus C. and Wohlin, Claes and Regnell, Björn},
  issn         = {0950-5849},
  language     = {eng},
  number       = {14},
  pages        = {831--839},
  publisher    = {Elsevier},
  series       = {Information and Software Technology},
  title        = {A project effort estimation study},
  url          = {http://dx.doi.org/10.1016/S0950-5849(98)00097-4},
  volume       = {40},
  year         = {1998},
}