LIMDEP and NLOGIT use extremely accurate computational methods throughout. The National Institute of Standards and Technology (NIST) has published a suite of about 50 benchmark tests with certified solutions for assessing program accuracy in computing descriptive statistics, analysis of variance, linear regression and nonlinear least squares regression. LIMDEP scores high marks on all of these. (See B.D. McCullough's review in the March, 1999 issue of Journal of Applied Econometrics.) Four of these tests are illustrated below.