Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
We develop a simple method for the estimation of quantile regressions for corner solutions data (i.e., fully observed non-negative data that have a mixed distribution with a mass-point at zero), focussing particular attention on the case where the domain of the variate of interest is bounded both from below and from above. We use the proposed method to study the determinants of the extensive margin of trade and find that most regressors have very different impacts on different parts of the distribution.