Improving the Connection between Theory and Empirical Analysis of Stated Preference and Conjoint Data: Improving Statistical Efficiency and Testing Robustness of Conjoint Marginal Valuations

We investigate the effect of panel estimators and sample weighting to improve efficiency of coefficient estimates and confidence intervals on marginal values. Panel estimators are appropriate because most conjoint studies have respondents rate multiple product profiles. Using a random effects ordered probit model increases significance levels on two forest health attribute coefficients and results in substantial tightening of confidence intervals on marginal values. To mitigate the effects of low response rate, we weight the returned surveys using Census data to match the sample to the population. Two of the four marginal values from this weighted ordered probit model are substantially different.