Previous: Commands and Data Required

Up: Commands and Data Required

Next: 2. Counterfactual evaluation.

1. Evaluation.

To evaluate an electoral system, the basic model requires that you specify a dependent variable such as a column of vote proportions (using the YVOTE keyword) and a set of explanatory variables (using XVARS). The input of this information also allows estimation of SIGMA.

To estimate LAMBDA, you need to specify the vote proportion for the election following the one in the election you are analyzing if available (using YVOTE2). JudgeIt estimates LAMBDA by regressing this next election vote proportion on the original vote proportion dependent variable (the coefficient of which is the estimate of LAMBDA) and the original explanatory variable. If you wish to include other variables in the regression to estimate LAMBDA, specify XVARS2. The PRELIM command takes care of all these steps; all you need to do is define your data correctly (with YVOTE, XVARS, YVOTE2, and XVARS2) and call the PRELIM command. See below for the commands used to choose the desired form of statistical output.