have a positive influence on the profitability of firms. This study examines the effect of product diversification on the … profitability of 25 German food industry sectors from 1977 to 1994. The analysis reveals a positive effect of diversification on the … profitability of industries. …

if they are not. We present empirical evidence on effects of perceived threat of entry on profitability. Using … profitability is confirmed. The number and the relative size of competitors also exert considerable effects. We find no …

optimal. When eradication is feasible, the optimal program requires either a low vaccination rate or eradication. A high … vaccination rate is never optimal. Under special conditions, the results are especially stark: the optimal policy is either not to …

hospitalisation and fatality rates of vaccination and population immunity due to past infection: the latter was the most signiÖcant … factor driving both trends, while the vaccination rate also had a signiÖcant short run e§ect on the fatality rate. We also …

private university allows us to estimate how peer effects influence health beliefs and vaccination choices. Our results … positive peer effects on individuals' vaccination decisions. A student becomes up to 8.3 percentage points more likely to get … inoculation clinics suggests that students coordinate their vaccination decisions with their friends. …