Can Small Firms Find and Defend Strategic Niches? A Test of the Porter Hypothesis
检验波特假说，发现当大小企业产品组合不同时，大企业利润率优势消失，但市场领导者仍保持优势。
A number of studies have found a positive relation between market share and profitability. Michael Porter argues that this need not hold when small firms find strategic niches protected by mobility barriers. This paper examines that hypothesis by comparing the profitability of large and small lines of business when the activities of the two groups (proxied by the allocation of sales across submarkets) differ on average. We find that in heterogeneous product mix industries profits of large LBs are no longer significantly greater than profits of smaller rivals, except that market leaders maintain their advantage regardless of product mix.