Research for Information Theory

Syndicate content
THE PREDICTION OF ATTRITION FROM MILITARY SERVICE
December 1, 1978
This paper provides a comparison of four statistical models for predicting first-year attrition from the Navy. The models compared are the individual linear probability model, the grouped linear probability model, the individual logit probability model and the grouped logit probability model. For different qualifying scores, the models are compared in terms of their ability to discriminate between attriters and non- attriters. Their ability to predict the actual attrition rates within future entry cohorts is also compared.
Read More | Download Report
LOTKA'S FREQUENCY DISTRIBUTION OF SCIENTIFIC PRODUCTIVITY
March 1, 1978

In 1926, Alfred Lotka examined the frequency distribution of scientific productivity of chemists and physicists. After analyzing the number of publications of chemists listed in Chemical Abstracts 1907-1916 and the contributions of physicists listed in Auerbach's Geschichtstafeln der Physik, he observed that the number of persons making n contributions is about 1/n squared of those making one and the proporation of all contributors that make a single contribution is about 60 percent. Recently, investigator's studying the applicability of 'Lotka's Law' to the humanities and to map librarianship may have misinterpreted Lotka's Law and have concluded erroneously that the law applies to these fields. Corrected calculations indicate that Lotka's Law does not apply.

Read More | Download Report
SEMI-MARKOV PROCESSES, AN INTRODUCTION
October 1, 1977
This research contribution describes the basic methodology for analyzing semi-Markov processes and demonstrates how to solve the necessary equation numerically. Two mechanisms for producing semi-Markov processes are described and examples presented. Algorithms needed to analyze semi-Markov (continuous- and discrete-time) processes are derived.
Read More | Download Report
THE EXACT DISTRIBUTION OF A SMIRNOV STATISTIC
April 1, 1977
The exact distribution is given for the number of times the vertical steps of an empirical distribution cross the underlying theoretical distribution. The statistic was used for Smirnov [1] to derive limiting distributions of statistics used in Kolmogorov-Smirnov tests, and may be used as a goodness-of-fit test in its own right.
Read More | Download Report
EXPERIMENTAL VALIDATION OF PROBABILITY PREDICTIONS
September 1, 1976
The purpose of this paper is to derive the methodology for using classical test statistics in the validation of simulation models (such as probability of a particular occurrence) using a small, varied data base.
Read More | Download Report
A Procedure for the Evaluation of Proposals
August 1, 1974
This research contribution provides an impartial and objective method for selection of the best among several research and development proposals. It provides for a statistically designed evaluation of the proposals by a review board followed by analysis of the evaluation scores by an analysis group. Included are guidance for selection of points for evaluation, a check list of tasks to be accomplished, and full instructions for mathematical analysis of the evaluation scores.
Read More | Download Report
A BAYESIAN APPROACH TO DEMAND ESTIMATION AND INVENTORY PROVISIONING
August 1, 1974
This research contribution addresses the problem of explicitly taking into account uncertainty about the demand for spare parts in making inventory procurement and stockage decisions. The model described provides for a unified treatment of the closely related problems of statistical estimation of demand and resource allocation within the inventory system, and leads to an easily implemented, efficient method of determining requirements for spare parts both in the early provisioning phase and in later periods of operations when demand data has accumulated.
Read More | Download Report
MARKOV Duels
June 1, 1974
This paper develops duel models for the situation in which the outcomes from a finite stationary Markov chain and both weapons have an unlimited supply of ammunition, fire at constant intervals of time, and duel until one is killed.
Read More | Download Report
AN APPROACH TO SEMI-MARKOV PROCESSES
June 1, 1974
This paper reports on some of the mathematical results that the author obtained while seeking to refine the Markov chain models used in air ASW tactical analyses in numerous studies done at CNA. In an effort to take into account the waiting time in each state prior to transition, a non-Markov process was postulated. Subsequent investigation showed the process to be a reformulation of a semi-Markov process.
Read More | Download Report
ON A THEOREM OF WEYL
June 1, 1974
If A is a Lebesque measurable subset of the interval (O,1) and t is any irrational number in that interval, then by a well-known theorem of Weyl, the frequency with which the integer products of t modulo one fall in A converges to the measure of A. This result may be used to evaluate asymptotic error in certain approximations. For a special case, Weyl's theorem is shown to extend to rational numbers t and a lower bound on frequency is derived.
Read More | Download Report