An experiment in which 150 proposals submitted to the National Science Foundation were evaluated independently by a new set of reviewers indicates that getting a research grant depends to a significant extent on chance. The degree of disagreement within the population of eligible reviewers is such that whether or not a proposal is funded depends in a large proportion of cases upon which reviewers happen to be selected for it. No evidence of systematic bias in the selection of NSF reviewers was found.

Gingival recession studies in the U.S. have related primarily to sex and age with little consideration of toothbrush hardness. This preliminary study examined the relation between a history of hard toothbrush use and gingival recession. A total of 182 subjects, male and female, between 18 and 65 years of age, with a minimum of 18 natural teeth, no advanced periodontitis or history of periodontal surgery were examined. Gingival recession was scored as present whenever the free gingival margin was apical to the cemento-enamel junction and root surface was exposed. History of hard toothbrush use was ascertained. Eighty-two subjects had a history of hard toothbrush use, 77 did not, and 23 did not know. The percentage of subjects with recession increased with age from 43% to 81%, with a figure of 63% for all age groups combined. Males tended to show slightly greater levels of recession than females. Regression analysis showed that females had about 4 percentage points less receded surfaces than males. Recession was also found to be more pronounced for subjects with a history of hard toothbrush use, with a mean of 9.4% receded surfaces versus 4.7% for those who had never used a hard brush. For users of hard toothbrushes, the percent of surfaces with recession showed a significant and dramatic increase with increasing brushing frequency; this effect did not exist for those without a history of hard brush use. The relation with age was highly significant, with regression analysis showing that the percent of surfaces with recession tends to increase about 3.5 percentage points per decade.(ABSTRACT TRUNCATED AT 250 WORDS)

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This paper analyzes the impact of e-commerce on markets where established firms face competition from Internet-based entrants with focused offerings. In particular, we study the retail brokerage sector where the growth of online brokerages and the availability of alternate sources of information and research services have challenged the dominance of traditional brokerages. We develop a stylized game-theoretic model to analyze the impact of competition between an incumbent fullservice brokerage firm with a bundled offering of research services and trade execution and an online entrant offering just trade execution. We find that as consumers' willingness-to-pay for research declines, the incumbent finds it optimal to unbundle its offering when competing with the online entrant. We also find that the online entrant chooses a lower quality of trade execution when faced with direct competition from the incumbent's unbundled offering. The analytical model motivates a unique field experiment placing actual simultaneous trades with traditional full-service and online brokers, to compare order handling practices and the quality of trade execution. In keeping with our analytical results, our empirical findings show a significant difference in the quality of execution between online brokerages and their full-service counterparts. We discuss the relevance of our findings for quality differentiation, price convergence and profit decline in a variety of markets where traditional incumbents are faced with changes in the competitive landscape as a result of e-commerce.