Selection of Dose Levels for Estimating a Percentage Point of a Logistic Quantal Response Curve

Experimental designs are presented for estimating an extreme percentage point of a logistic distribution when the observations are quantal responses and the location and scale parameters are unknown. The method is based on a prior distribution of the parameters and a predicted value of the posterior variance. The paper is an extension of an earlier article (Tsutakawa, 1972) for the case when the scale parameter is known.