Information systems and health statistics deal with data which have been ordered and received a name, so that they can be counted. What has no name, cannot be counted and consequently has no impact. ICPC, together with its manual provides the best available tool to order and to name essential elements of primary care. It offers a widely tested, comprehensive classification system which can be used in three modes:

as a Reason for Encounter classification

as a Diagnostic classification

as a Process classification.

Summary

The maximum likelihood (ML) estimator and its modification in the linear functional relationship model with incidental parameters are shown to be third-order asymptotically efficient among a class of almost median-unbiased and almost mean-unbiased estimators, respectively, in the large sample sense. This means that the limited information maximum likelihood (LIML) estimator in the simultaneous equation system is third-order asymptotically efficient when the number of excluded exogenous variables in a particular structural equation is growing along with the sample size. It implies that the LIML estimator has an optimum property when the system of structural equations is large.

Summary

Two sets of modified kernel estimates of a regression function are proposed: one when a bound on the regression function is known and the other when nothing of this sort is at hand. Explicit bounds on the mean square errors of the estimators are obtained. Pointwise as well as uniform consistency in mean square and consistency in probability of the estimators are proved. Speed of convergence in each case is investigated.

Maps constructed from seismic data represent subsurface structures in terms of two-way transit time. Wireline logs provide depth of formation tops at well locations. The best representation of a subsurface horizon should combine both measurements. Kriging is an ideal tool for merging seismic and log data.

This case history describes the mapping of a reef in north Texas. Seismic data include three common depth point (CDP) lines and a large number of single-fold records. Wireline logs, including a vertical seismic profile (VSP), are available in 11 wells.

The first step is the geostatistical analysis of seismic data. The empirical semivariogram is drawn from several hundred shot points, and a theoretical model is fitted. This semivariogram is used to construct a time grid.

In the second step, wireline logs are correlated to the seismic sections with the help of the VSP data. A time-depth relationship is established and applied to the time grid to yield a “drift” for the kriging of the depth data. The final output is a depth grid used to generate a contour map.