I have conducted a CBC study and estimated HB part worth utilities with LightHouse Studio. I am now building an Excel simulator and would like the Excel simulator to do linear interpolation between price levels tested in conjoint. For example, in conjoint we tested price levels: $2, $4, $6. In my Excel simulator, I want to be able to evaluate preference share for $4.50 which was not tested in conjoint/does not have a part worth utility from CBC HB.
My Excel simulator creates a design vector for each simulated product with value=1 for attribute levels selected for a product and value=0 for attribute levels not selected for a product. This is then multiplied by the utility vector using the SUMPRODUCT() formula to obtain Total utility for each simulated product. The 1/0 coding works for non-interpolated values BUT how do I code the design vector for interpolated values? For example, is this the correct way to code the design vector for $4.50?
Step 1. Proportion of utility range for $4.50: ($4.50-$4)/($6-$4)=0.25.
Step 2. Price attribute design vector (0, 0.75, 0.25) to be multiplied by utility vector: