Co-movements of index options and futures quotes

We report evidence that the co-movements of index options and index futures quotes differ sharply from perfect correlation in periods with option trades. In half-hour intervals with (without) option trades 25% (12%) of call option quote changes have either the opposite sign or are larger in magnitude than the corresponding index futures quote changes. We calibrate a stochastic volatility model that allows for trade and no-trade periods using real data and simulate the joint co-movements of index quotes and option quotes in this model. We show that for trade intervals the observed co-movements differ from the benchmark case established by our simulations approximately three times too often. We provide empirical evidence that market microstructure effects – specifically, stale quotes and aggressive quotes – explain the majority of the deviations from the benchmark. Our findings are relevant for techniques that use estimates of local co-movements as inputs to price or hedge options.     

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The influence of cultural context on the relationship between gender diversity and team performance: a meta-analysis

The impact of gender diversity on team performance has become a central topic in the field of human resource management for researchers and practitioners alike. Extant research provides conflicting evidence on the relationship between gender diversity and team performance. To resolve these contradictory findings, we meta-analyze the relationship between gender diversity and two performance outcomes, namely task performance and contextual performance. Grounded in categorization-elaboration model, we simultaneously consider the positive and negative aspects of gender diversity. We further examine the effect of cultural context as a moderator on the relationship between gender diversity and team performance. Based on 71 independent samples from 68 studies published between 1996 and 2013, we find a significant negative relationship ( ? 0.10) between gender diversity and contextual performance. Additionally, we find that the cultural dimensions gender egalitarianism and collectivism have significant moderating influences on the relationship between gender diversity and task performance.     

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