1386 JEM Vol. 203, No. 6, 2006 Helpless without SAP CD4+ T cells that lack the adaptor protein SAP are little help to B cells, according to Cannons and colleagues on page 1551. But their unhelpful nature does not result from a failure to produce T helper (Th)-2 cytokines, as the authors had previously thought. The absence of SAP wreaks havoc on the immune system. SAP—the adaptor that links the ...

The value of information technology (IT) in today’s organizations is constantly debated. Researchers and practitioners have examined organizations to try to discover causal links between competitive advantage and IT. This paper presents and details a model that depicts a possible connection between competitive advantage and IT. Furthermore, this paper attempts to show how one major component of...

What, if anything, is wrong with taking advantage of people’s unjust circumstances when they both benefit from and consent to the exchange? The answer, some believe, is that such exchanges are wrongfully exploitative. I argue that this answer is incomplete at best, and elaborate a different one: to take advantage of injustice is to become complicit in its reproduction. I also argue that the cas...

Winning business strategies are grounded in sustainable competitive advantage. A company has competitive advantage whenever it has an edge over rivals in securing customers and defending against competitive forces. There are many sources of competitive advantage: making the highest-quality product, providing superior customer service, achieving lower costs than rivals, having a more convenient ...

Thus Jacob Viner (1937, p. 442) balanced the claims of E. R. A. Seligman for Robert Torrens against those of J. H. Hollander for David Ricardo. Lionel Robbins (1958) found rather more in Torrens, and J. Chipman (1965) also made much of his contribution. W. O. Thweatt (1976) made a small sensation when he attributed Ricardo’s formulation to James Mill, regarded only as a popularizer of Ricardo’s...

A stylized model of trade between identical countries is developed, where the only departure from standard neoclassical theory is that worker skills are imperfectly observable. This creates an informational externality since firms take aggregate investments into consideration when making inference about individual workers. The interaction between the informational externality and price effects ...

From 2007 to June 2013, a small group of fee-paying, high-speed traders receive the Michigan Index of Consumer Sentiment two seconds before its broader release. Within this early peek window, we find highly concentrated trading and a fast price discovery of less than 200 milliseconds. Outside this narrow window, general investors trade at fully adjusted prices. We further establish a casual rel...

I explore the interactions between comparative, competitive and absolute advantage in a two-country model of oligopoly in general equilibrium. Comparative advantage always determines the direction of trade, but both competitive and absolute advantage affect resource allocation, trade patterns and trade volumes. Competitive advantage in the sense of more home firms drives foreign firms out of ma...

T he imprint of operations on a bank’s performance is hard to overstate—and extends well beyond the back office. Although the word operations implies something mechanical—perhaps impersonal—such activities and processes have a profound impact on customer satisfaction and retention. More than many other factors, operations influence how a customer views a bank. Years ago, pioneers in other indus...