where the variables are: Y is the consumer attitude towards the store brand; IL the store image (layout); IM the store image (merchandise); IS the store image (service); RFUN the functional risk; RPSY the psychosocial risk; RFIN the financial risk; b the regression coefficients; g the intercepts; and e is the error terms.
Before conducting the regressions following Eq. (1) the data were investigated on a descriptive level. Selected descriptives are reported in Table 1. It appears that AH has the best and most consistent store image amongparticipants:AHisfollowedbyEdahand finally by Aldi. A look at the means of consumers’ attitudes towards the store brand reveals that although AH attained the highest level, Edah and Aldi are at similar levels. These differences are clearly less pro- nounced than the ones between the different store images.
From Table 1 it became clear that the retailer sample is not homogeneous. It was therefore decided to create correlation matrices for the three retailers separately, including all core constructs, with the primary purpose of obtaining insight in the data structure. These matrices are presented in Table 2.
Significant correlations exist between most of the variables, the highest level being between attitude towards the store brand and perceived financial risk in the AH and Edah samples, and between attitude towards the store brand and store image in the Aldi Sample. This observation is an indication that it may not be allowed to pool the data for the three retailers. Before any further techniques could be applied, parameter stability over the three store brands had to be verified. F-tests (Chow, 1960) were thus applied to regressions according to model (1) of various combinations of the three partial samples. For that purpose, two dummy variables were introduced with the following values