EuroQol Working Paper, 07-12-2016

Combining continuous and dichotomous responses in a hybrid model

Ramos-Goñi JM, Craig BM, Oppe M, van Hout BA.

In survey research, continuous responses may represent a value, a lower or upper bound of a value, or a range of values (e.g., the value of my car is $10,000, is greater than or equal to $9,000 or is between $9,000 and $10,999). Dichotomous responses may represent an inequality in value (e.g., the value of my car is higher than the value of that car). Given a dataset with continuous and dichotomous responses, the hyreg command estimates the parameters of a hybrid regression model by maximizing a single likelihood function, namely the product of the likelihoods of continuous and dichotomous responses. Analogous to combining, for example, intreg and logit commands, this paper demonstrates the hyreg command using simulated data and includes an example of an econometric specification from health preference research.