Analysis of Sales Promotion Effects on Household Purchase Behavior

4.3.4 Storability/Perishability
Storable products facilitate stockpiling and therefore intertemporal purchase displacement.
Narasimhan et al. (1996) reported that promotions get the highest response for brands in
easily stockpiled categories, especially due to purchase acceleration. Raju (1992) concluded
that bulkiness (volume, which is inversely related to storability) and perishability both have a
negative impact on the variability in category sales. Bell et al. (1999) argued that storability
and purchase acceleration (both time and quantity) are positively related. They concluded that
all refrigerated products had much higher proportions for the time effect than for the quantity
effect and that all storable products showed the opposite pattern. Bucklin et al. (1998) argued
that purchase quantity effects could be smaller for perishable product categories. It is
therefore hypothesized that storability is positively related with promotional effects, mainly
due to purchase acceleration (H4). Perishability is negatively related with promotional effects
(H5).
4.3.5 Number <strong>of</strong> Brands
Narasimhan et al. (1996) observed a negative relationship between number <strong>of</strong> brands and
promotional elasticity, which they attributed to brand switching. The presence <strong>of</strong> many brands
reflects broader product differentiation, which, in turn, protects an individual brand from the
enticement <strong>of</strong>fered by a competitor’s promotion. Bawa et al. (1989), however, found that
larger assortments do tend to generate higher trial for new products. Bell et al. (1999) also
hypothesized that purchase acceleration effects are positively related to number <strong>of</strong> brands
within a category. We expect to find a positive relationship between number <strong>of</strong> brands and
promotional effects (H6).
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