ECONOMETRIC STUDY OF THE DEMAND FOR HIGHER EDUCATION IN CANADA, 1976-1995 Column D tests a different aspect of the specification, the assumption that the background characteristics predicting SAT scores are identical to those indexing willingnessto- pay for desirable schools. To test this, I allow willingness-to-pay to depend on students self-reported family income, estimating the interaction between income and Tiebout choice while including the peer quality index to absorb peer effects. The interaction coefficient here is again negative and insignificant
