The investigator, Herman Chernoff, will continue his work in sequential analysis. One problem is that of deciding the sign of m, the drift of Brownian motion. Assuming the cost of a wrong decision to be independent of m and the sampling cost to be proportional to time multiplied by the square of the drift for bounded sampling time. Chernoff will examine the effect of normal priors and mixtures of normal and point mass priors form. Another problem to be investigated is that of serial dependence in quality control. Chernoff will also examine a robust method for the problem of missing explanatory variables in a regression model. In the area of simulation the Chernoff will study the asymptotic validity of the "bootstrap" method as well as a two- stage approximation of a posterior distribution. It is hoped that these and other statistical methods will prove useful in problems in astronomy. He will also study the possibility of applying data analytic and pattern recognition techniques to the identification of common subsequences in long strings that occur in biological problems.