To form an indicator of the relative switcher generation
potential of the retailers, we observe that a bookstore that
wants to attract more switchers may be listed more often in
a price comparison query. For a particular set of price comparison
sites, we formulate a retailer’s search share as the
proportion of price comparison sites that return prices for
that retailer. Greater search share means that the retailer is
listed on more book price comparison sites and thus may
attract more switchers from various segments. Although
search share does not differentiate switcher segment sizes, it
gives a firm-specific indication of switcher intensity (SLR
incorporates the sum of a retailer’s switcher segment sizes).
We use the nine top-ranked book price comparison sites and
mySimon to formulate a list of price comparison sites for
books.12 There are several reasons a firm might be listed in
a price comparison engine. Sometimes, a price comparison
site uses a retailer’s prices without specific action on the
part of the retailer. In addition, relatively high-cost retailers
are not necessarily absent from price comparison sites. A
firm with comparably higher prices may want greater
access to all potential buyers, and therefore it may share its
pricing data with the search engine (Iyer and Pazgal 2003).
Whether retailers are high priced or low priced, those listed
in price comparison sites have access to a greater number of
switchers. Therefore, the degree of participation in price Deletcomparison
engines serves as an indicator of the retailer’s
access to switchers who become informed of its prices.