While a large literature has studied how people make
forecasts, less is known about how lay people process
and interpret forecasts presented to them. We contrast
two common ways of communicating an uncertain fore-
cast, as either a chance (e.g., the probability of winning)
or as an expected margin (e.g., the point spread). Across
five studies, we find a robust chance-margin discrepan-
cy: people tend to treat a chance forecast as conveying
greater probability of the higher-likelihood outcome than
the statistically equivalent margin forecast
