More choice is better: Effects of assortment size and composition on assortment evaluation Harmen Oppewal a, * , Kitty Koelemeijer b,1 a Department of Marketing, Monash University, P.O. Box 197, Caulfield East, Vic 3145, Melbourne, Australia b Center for Supply Chain Management, Nyenrode University, Straatweg 25, 3621 BG Breukelen, The Netherlands Abstract This study focuses on effects of assortment size and composition on assortment evaluation. Data from a choice experiment conducted with members of a large consumer panel suggest that adding any item improves assortment evaluation, regardless of their attributes or the size of the assortment. Although effects are observed for a few specific products, there is no evidence of a generic dfavorite availableT effect as reported in earlier studies, nor is there indication that smaller assortments suffice if they contain a consumer’s favorite alternative. D 2004 Elsevier B.V. All rights reserved. Keywords: Retailing; Store assortments; Consumer purchase behavior; Store image; Assortment perception 1. Introduction One of the most important ways in which retailers add value to products is by making assortments available to consumers. In the light of this, retailers have typically assumed that larger assortments pro- vide more benefits to consumers than smaller assort- ments. Retailers are, however, becoming increasingly aware of the costs of carrying larger assortments. Operational costs go up with the numbers of stock keeping units (SKUs) and stores offering a very limited assortment, such as the ALDI discount stores, are performing well. Retailers are also increasingly keen to recognize opportunities for smaller-scale outlets with reduced size assortments. Such outlets allow retailers to locate at sites that otherwise would never fit their formats. Examples include IKEA, which has moved into Manhattan with a reduced size outlet (Pellet, 1995) and Laura Ashley, which has opened smaller properties for homewares outside its traditional store locations in the UK (Retail Week, 2000). Recent research suggesting that retailers can reduce their number of SKUs without any detrimental effect on sales greatly interests retailers. Sales can even increase when items are deleted from the assortment 0167-8116/$ - see front matter D 2004 Elsevier B.V. All rights reserved. doi:10.1016/j.ijresmar.2004.03.002 * Corresponding author. Tel.: +61 3 990 32360; fax: +61 3 990 31558. E-mail addresses: Harmen.Oppewal@buseco.monash.edu.au (H. Oppewal)8 K.Koelemeijer@nyenrode.nl (K. Koelemeijer). 1 Tel.: +31 346 291249; fax: +31 346 291250. Intern. J. of Research in Marketing 22 (2005) 45 – 60 www.elsevier.com/locate/ijresmar