You can now compute your own forecasts based on the bio-index model, which predicts the election outcome based on information about candidates' biographies. This feature allows you See how the model forecast would change for different variable coding. Compare two hypothetical candidates against each other....
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For some models, Polly now allows you to manipulate the variable values and compute your own model forecasts. For now, this is available for the Fair model and Lichtman's Keys.