Presents two statistical topics and examples of their use in natural resource monitoring. The first topic deals with use of correlated observations in calculations of variance estimates for a regional mean, required sample size determination, and confidence intervals. The second topic concerns the use of Bayesian techniques in hypothesis testing.…

The sampling errors of maximum likelihood estimates of item-response theory parameters are studied in the case where both people and item parameters are estimated simultaneously. A check on the validity of the standard error formulas is carried out. The effect of varying sample size, test length, and the shape of the ability distribution is…

Teacher-made mastery tests were administered in a classroom-sized sample to study their decision consistency. Decision-consistency of criterion-referenced tests is usually defined in terms of the proportion of examinees who are classified in the same way after two test administrations. Single-administration estimates of decision consistency were…