In my last post analyzing my own forecasting history on Inkling Markets, I showed that I was consistently identifying long-shot bets that were more likely to pay off than their existing probability would suggest. In this post, I'll look at how my forecasts improve the accuracy of these markets, calculating how many the change in component Brier score within different percentiles.
We're developing some new tools to analyze forecasters' performance, biases, and ways to help them improve, and I've been digging into my own forecasting history on Inkling. I've focused on a set of 3,343 forecasts I've made in questions that use an LMSR algorithm and have already resolved. The first interesting finding is that most of my forecasts have been wrong.
Prediction markets are generally very good at generating accurate forecasts, but a key secondary challenge is to determine which forecasters are contributing most to forecast accuracy. User scores are closely linked to their accuracy because the underlying market mechanism rewards users when they move a forecast closer to its actual result and penalizes them when they move the forecast away from the result.