Image: Flickr/Images MoneyWhen it comes to playing the odds, there are times when gambling feels more enticing than others. But is there a pattern to when people indulge in games of luck and when they abstain? Well, according to this study, there is! Apparently, when other circumstances dictated by "luck" are going well, people are more likely to play the lottery. Specifically, they found that people are more likely to play the lottery during a long string of sunny days, or when a local sports team is playing well. So, if you don't want to share the pile of money with another winning ticket, your best bet may be to play when the weather's bad or the Yankees are losing.Unexpected but Incidental Positive Outcomes Predict Real-World Gambling "Positive mood can affect a person’s tendency to gamble, possibly because positive mood fosters unrealistic optimism. At the same time, unexpected positive outcomes, often called prediction errors, influence mood. However, a linkage between positive prediction errors—the difference between expected and obtained outcomes—and consequent risk taking has yet to be demonstrated. Using a large data set of New York City lottery gambling and a model inspired by computational accounts of reward learning, we found that people gamble more when incidental outcomes in the environment (e.g., local sporting events and sunshine) are better than expected. When local sports teams performed better than expected, or a sunny day followed a streak of cloudy days, residents gambled more. The observed relationship between prediction errors and gambling was ubiquitous across the city’s socioeconomically diverse neighborhoods and was specific to sports and weather events occurring locally in New York City. Our results suggest that unexpected but incidental positive outcomes influence risk taking." Related content: NCBI ROFL: Never smile at a crocodile: betting on electronic gaming machines is intensified by reptile-induced arousal. NCBI ROFL: Understanding russian roulette FAIL. NCBI ROFL: Surprising study finds that little old ladies enjoy playing bingo.