# Solved – Interpreting exp(b)

With respect to (binary) logistic regression and a categorical IV, State, if a given exp(b) is .08 and I'm using indicator coding such that my reference category for the variable, State, is, say, "Wyoming," how do I interpret .08? Presumably I contrast the .08 with the "mean" of Wyoming (with "mean" here being the proportionality, or number of positive instances, of Wyoming)…So if Wyoming = .06, do I multiply .08 * .06 = .0048? That doesn't quite feel right…

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Let's imagine your response variable is `percent urban`, and that the mean of this variable in Wyoming is \$.06\$. Since each person lives in an urban area or not, this means that \$6%\$ of the population lives in an urban area. You fit a logistic regression model to predict `percent urban` based on `state`, where Wyoming is the reference level, and you have one other state, say Montana. The analysis returns an estimated coefficient, \$hatbeta_text{Montana}\$, and \$exp(hatbeta_text{Montana})=.08\$.