The purpose of this section is to compare what managers perceived the total cost to be (survey) and what the researcher found from a thorough investigation and quantification of the total cost (case studies).
The average of the percentage of the price, as a part of total ongoing cost, in case companies was 65.6 per cent (standard deviation 20.9), while that of the price in the survey respondent companies was 80.0 per cent (standard deviation 13.0). In order to test whether the mean of the per cent of price in case companies is smaller than that in survey companies, a t-test (independent two-sample t-test, unequal sample sizes) was carried out.