We examine gender differences in trust in another party's cooperation (CC) or its ability (AC). While men and women do not differ concerning trust in cooperation, gender has a strong influence when trust in another subject's ability is required.

We analyze the gender wage gap in experimental markets. Women receive but do not request significantly lower wages than men. This hurts firms, as women react with low effort. Additionally, women tend to react differently than men to wage levels.

Providing incentives to subjects in internet experiments can be tricky. One simple method is a high score (as in computer games). We test whether high scores provide adequate incentives in comparison to the usual performance based incentives. We find significant differences.

We describe an ambiguity hedging problem in Ellsberg experiments, where combinations of individually ambiguous bets eliminate aggregate ambiguity, and which may yield incorrect classifications of ambiguity averse subjects. We propose a new classification consistent with this hedging possibility.