PhD Final Thesis April 2013.pdf - Anglia Ruskin Research Online

Thesis Keith Gale 20137.12 Analysis of results – structure and descriptorsResults from the raw data showing outcomes of projects in Appendix 9 have beensynthesised into five critical success factors stated in Table 7.8. Outcomes arecalculated as numerical values described in paragraphs 7.9.1 to 7.9.5 and weighted inaccordance with ratios in Table 7.8. Aggregation of weighted critical success factorsallows a project success index to be given by numerical value. A data sheet for allprojects showing CSF’s and PSI’s is at Appendix 10.In order to statistically explore relationships between the two groups – discrete andframework projects - independent samples t-tests are applied to values taken from thedata sheet. With all t-tests the following descriptors are applied:• Dependant variables are measured at interval levels using continuousresults.• The projects represent all of the population of highways infrastructureschemes undertaken by the organisation between May 2006 and December2010.• All observations are independent of one another and supported byindependent evidence. There is no interaction between results from any ofthe five critical success factors and random sampling confirms this.• The populations are assumed to be statistically normally distributed.7.13 Variations to results caused by project characteristicsStudies into outcomes with projects in the construction industry tend to aggregateresults in a simple form, with only a cursory review of the characteristics that mayaffect performance. This is often due to the limitations of research methods used orquality of available data (Molenaar and Songer, 1998). Hair et al, (2006) recognisedthat projects with mixed characteristics included within an independent variablewould only show a single relationship. The effect of project characteristics uponproject performance formed a study undertaken by Cho et al, (2009) withconclusions that a few characteristics could significantly affect performance. The147