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Showing papers on "Reliability (statistics) published in 1973"


Journal ArticleDOI
TL;DR: A Bayesian reliability growth model is presented which includes special features designed to reproduce special properties of the growth in reliability of an item of computer software (program).
Abstract: A Bayesian reliability growth model is presented which includes special features designed to reproduce special properties of the growth in reliability of an item of computer software (program). The model treats the situation where the program is sufficiently complete to work for continuous time periods between failures, and gives a repair rule for the action of the programmer at such failures. Analysis is based entirely upon the length of the periods of working between repairs and failures, and does not attempt to take account of the internal structure of the program. Methods of inference about the parameters of the model are discussed.

451 citations



Book
01 Jan 1973

313 citations



Journal ArticleDOI
TL;DR: Reliability of observational data was measured simultaneously by two assessors under two experimental conditions, indicating that observers modified their observational criteria to approximate those of the identified assessor.
Abstract: Reliability of observational data was measured simultaneously by two assessors under two experimental conditions. During overt assessment, observers were told that reliability would be measured by one of the two assessors, thus permitting computation of reliability with an identified and an unidentified assessor. During covert assessment, observers were not informed of the reliability measured. Throughout the study, each of the assessors employed a unique version of a standard observational code. In the overt assessment condition, reliability of observers with the identified assessor was consistently higher than reliability with the unidentified assessor, indicating that observers modified their observational criteria to approximate those of the identified assessor. In the covert assessment condition, reliability with the two assessors was substantially lower than during overt assessment. Further, observers consistently recorded lower frequencies of disruptive behavior than the two assessors during covert assessment.

186 citations



Journal ArticleDOI
TL;DR: The program presented here performs an automatic indexing of powder patterns by means of a trial-and-error method that has been optimized and presents a good flexibility.
Abstract: The program presented here performs an automatic indexing of powder patterns by means of a trial-and-error method. It has been optimized and presents a good flexibility. It can account for various additional information, known a priori. In addition, extensive error computations are included in it, leading to a good reliability, even with some incidental errors. Moreover its input and printout have been implemented so that the program can be easily used even by non-specialists.

134 citations


Journal ArticleDOI
TL;DR: A matrix formulation of the reliability analysis and reliability-based design of structures is developed and can be used by designers to choose among alternative designs that satisfy all existing code regulations, and to design systems in the absence of formal code regulations.

105 citations


Journal ArticleDOI
TL;DR: In this paper, modifications of the two-sided one-sample Kolmogorov-Smirnov "goodness-of-fit" test, for use with censored and truncated samples, are suggested.
Abstract: Modifications of the two-sided one-sample Kolmogorov-Smirnov “goodness-of-fit” test, for use with censored and truncated samples, are suggested. Tables of the distributions of the modified statistics are given. Applications to life testing and reliability estimation problems are discussed.

101 citations



Journal ArticleDOI
TL;DR: In this article, the importance of risk and uncertainty considerations in structural evaluation and design is emphasized, and practical methods for risk assessment in terms of failure probability and for development of reliability-based design criteria are described and developed.
Abstract: Existing probability bases of reliability analysis and reliability based design are summarized The importance of risk and uncertainty considerations in structural evaluation and design are emphasized, and practical methods for risk assessment in terms of failure probability and for development of reliability-based design criteria are described and developed Advocates the systematic analysis of uncertainty through first-order statistical analysis, and the explicit use of failure (or survival) probability as measure of risk and safety, to fully realize the potentials of probability theory in structural evaluation and design

Journal ArticleDOI
TL;DR: The AICPA requires all auditors to initially evaluate the reliability of internal controls as a matter of audit standards as discussed by the authors, but the auditor does not possess a means to objectively evaluate the internal control system.
Abstract: The primary purpose of incorporating a set of internal controls in the financial information system is to enhance the system's reliability-i.e., to maintain a high probability of preventing, detecting, and eliminating errors, irregularities, and fraud in the financial information system. The demonstrated reliability of the system provides evidence as to the quality of the output of the system. It is well accepted that the effectiveness of internal controls must be taken into account in determining the extent and nature of the audit procedures appropriate in a given examination.' The more reliable the system, the less extensive the tests the auditor need conduct. Recognizing this inverse relationship between effectiveness of internal control and audit scope, the American Institute of CPAs requires all auditors to initially evaluate the reliability of internal controls as a matter of audit standards.2 Recently, the Committee on Auditing Procedures of the AICPA released several statements on the subject of internal controls which re-emphasize the importance of the study of their reliability.3 But, despite this emphasis, the auditor currently does not possess a means to objectively evaluate the reliability of the internal control system. Conventionally, the auditor uses questionnaires, flow charts, and tests of transactions for evaluation pur-

Book
15 Sep 1973
TL;DR: In this article, the authors discuss background and historical development, background and background development, Resume of the contents of the Monograph, and references of the monograph's authors.
Abstract: This chapter contains sections titled: Introduction, Background and Historical Development, Resume of the Contents of the Monograph, References

Journal ArticleDOI
TL;DR: The authors showed that the use of normalized ranks or, in the case of large numbers of categories, normal deviates results in an increasing, monotonic relationship between reliability and number of categories.
Abstract: THE psychological literature is rich with studies demonstrating that collecting responses to affective stimuli using a large number of ordered categories is not effective when compared with using some smaller number (e.g., Matell and Jacoby, 1971; Komorita and Graham, 1965). Thus, a 20-point scale is no better, and perhaps worse, in terms of reliability and validity than, say, a 5-point scale. However, these studies uniformly rank the categories and analyze these ranks. There is a small, circumscribed body of literature (Liu, 1971 ; Warren, Klonglan, and Sabri, 1969) which indicates that the use of normalized ranks or, in the case of large numbers of categories, normal deviates results in an increasing, monotonic relationship between reliability and number of categories. Such transformations weight highly response differences in the ends of the scale

Journal ArticleDOI
TL;DR: A questionnaire study and an observational study were conducted to investigate reliability among physical therapists in diagnosing and treating gait deviations in hemiplegics.
Abstract: A questionnaire study and an observational study were conducted to investigate reliability among physical therapists in diagnosing and treating gait deviations in hemiplegics. In Study 1, groups of...

Journal ArticleDOI
TL;DR: In this paper, nonverbal interactions of six married couples were observed and rated simultaneously, live and from a video monitor by two pairs of observers, and the results indicated that reliability of video observations is as high as for live observations of the same behavior.

Journal ArticleDOI
TL;DR: This experiment tested the utility of agreement as a method to separate stutterings and disfluencies into two reliable and unambiguous response classes.
Abstract: This experiment tested the utility of agreement as a method to separate stutterings and disfluencies into two reliable and unambiguous response classes. Reliability was determined by measures of in...

Journal ArticleDOI
TL;DR: In this article, a new formulation for the problem of system reliability optimization when constrained by some linear constraints is presented, which is easily adaptable to geometric programming form and is further reduced to that of an optimization of an unconstrained objective function with variables one less than the number of constraints, when its dual is defined.
Abstract: A new formulation for the problem of system reliability optimization when constrained by some linear constraints is presented in this paper. The formulation provided is easily adaptable to geometric programming form. The problem is further reduced to that of an optimization of an unconstrained objective function with variables one less than the number of constraints, when its dual is defined. It is amply demonstrated through this paper that the formulation and approach of this paper are simpler than earlier attempts described elsewhere. An example is also given.

Journal ArticleDOI
TL;DR: In this article, a computer program is presented to facilitate the reliability evaluation of large power systems, based on an extension of the minimal-cut approach for computing reliability, to cover models that can account for switching after faults.
Abstract: Approximation methods and a computer program are presented, to facilitate the reliability evaluation of large power systems The approximations are based on an extension of the minimal-cut approach for computing reliability, to cover models that can account for switching after faults The program can select the required "minimal-cut" failure states through an analysis of the failure effects in every state, and calculate the overall system reliability indices, if certain system failure criterial apply

01 Jan 1973
TL;DR: This document describes the physical properties of fatigue and its applications in the sport of tennis and aims to provide a chronology of these activities over a period of years.
Abstract: Keywords: mecanique ; fatigue ; fiabilite Reference Record created on 2005-11-18, modified on 2011-09-01


Journal ArticleDOI
TL;DR: In this article, a general index of reliability, termed canonical reliability, is developed for use with profiles, or more generally, for use of vectors of random variables, defined as the ratio of the average squared distance among true scores to the average square root of observed scores.
Abstract: A general index of reliability, termed “canonical reliability,” is developed for use with profiles, or more generally, for use with vectors of random variables. Canonical reliability is defined as the ratio of the average squared distance among true scores to the average squared distance among observed scores. Based on Mahalonobis distances, canonical reliability is shown to be consistent with multivariate analogues of parallel form correlations, squared correlation between true and observed scores, and an analysis of variance formulation. The index of reliability based on Cronbach and Gleser'sD 2 is also derived from the general formulation. A comparison of the Mahalonobis andD 2 approaches indicates that score vectors usingD 2 distances are more reliable; however, both methods of comparing profiles are useful depending on the nature of the information that is desired. Transforming the observed variables to independent canonical variates provides a basis for comparing profiles on maximally reliable profile dimensions. For illustrative purposes, profile reliability is calculated and interpreted for the WISC subscales for a 7 1/2 year age group.

01 Jan 1973
TL;DR: Any degree of uncertainty over these events or the information can be quantified into numerical probabilities, which can then be readily and accurately communicated within the system.
Abstract: : Within intelligence systems, it is important to assess the probability that certain events will occur and to determine the reliability of information on them. Any degree of uncertainty over these events or the information can be quantified into numerical probabilities, which can then be readily and accurately communicated within the system. Four advantages which stem from using numerical probabilities are discussed.

01 May 1973
TL;DR: The TEXAS HIGHWAY DEPARTMENT as mentioned in this paperPSD-13 (CFHR) as mentioned in this paper was developed to adapt the performance of the FPS-7 program to a specific level of reliability.
Abstract: A MAJOR PROBLEM IN PAVEMENT DESIGN HAS BEEN THE INHERENT UNCERTAINTY AND VARIATION OF THE DESIGN PARAMETERS AND MODELS. EMPIRICAL SAFETY FACTORS AND JUDGEMENT FACTORS HAVE BEEN APPLIED TO "ADJUST" FOR THE UNCERTAINTIES INVOLVED, BUT THE RESULT HAS BEEN MUCH OVERDESIGN AND UNDERDESIGN. A METHOD WAS NEEDED WHICH WOULD CONSIDER THE VARIATIONS AND UNCERTAINTIES OF PAVEMENT DESIGN QUANTITATIVELY AND MAKE IT POSSIBLE TO DESIGN FOR A SPECIFIC LEVEL OF RELIABILITY. AS A BASIC START IN THE SOLUTION OF THE PROBLEM, A THEORY AND PROCEDURES WERE DEVELOPED, BASED ON CLASSICAL RELIABILITY THEORY, TO APPLY PROBABILISTIC DESIGN CONCEPTS TO FLEXIBLE PAVEMENT SYSTEM DESIGN. THE PROBABILISTIC THEORY AND PROCEDURES HAVE BEEN BOTH PRACTICAL AND USEFUL AS THEY HAVE BEEN IMPLEMENTED INTO THE PAVEMENT DESIGN OPERATIONS OF THE TEXAS HIGHWAY DEPARTMENT. ORIGINAL IMPLEMENTATION WAS WITH THE DETERMINISTIC FPS-7 PROGRAM, WHICH WAS MODIFIED TO INCLUDE SOME PROBABILISTIC DESIGN CAPABILITY AND RENAMED FPS-11. THAT VERSION, WHICH HAS BEEN USED BY TEN DISTRICTS OF THE TEXAS HIGHWAY DEPARTMENT SINCE LATE 1971, HAS BEEN FURTHER DEVELOPED TO INCLUDE VARIATIONS OCCURRING IN INDIVIDUAL PAVEMENT LAYERS AND SUBGRADE, AND THE CONSIDERATION OF TRAFFIC FORECASTING ERROR. THE OVERLAY MODE WAS IMPROVED BY MAKING IT POSSIBLE TO "ADJUST" THE PERFORMANCE MODEL TO A SPECIFIC PAVEMENT BY CONSIDERING ITS PAST PERFORMANCE HISTORY, AND THE NEW PROGRAM WAS NAMED FPS-13 (CFHR).


Journal Article
TL;DR: In this article, the authors provide management with an overview of product reliability and related areas by providing charts which show the expected relation of part count to laboratory test results and the expected relations of laboratory test result to operational performance.
Abstract: This paper provides management with an overview of product reliability and related areas. Charts are provided which show the expected relation of part count to laboratory test results and the expected relation of laboratory test results to operational performance. These charts are followed by laboratory and operational material used in the development of the overview charts.

Journal ArticleDOI
TL;DR: In this article, the development of a measure of simulated personal space, using standardized instructions, is described and reliability and validity of the measure are evaluated. But this measure is not suitable for indoor environments.
Abstract: The development of a measure of simulated personal space, using standardized instructions, is described. Reliability and validity were assessed.


Journal ArticleDOI
TL;DR: In this article, the authors discuss the risks of introducing bias, the reliability of the data, and the resources required for these methods of grazing are discussed, and criteria are described for choosing between the methods.
Abstract: Pasture experiments may be grazed using either variable (put-and-take) or fixed stocking rates. Considerations such as the risks of introducing bias, the reliability of the data, and the resources required for these methods of grazing are discussed, and criteria are described for choosing between the methods.

Journal ArticleDOI
TL;DR: A titrimetric method for the determination of urinary bicarbonate is presented and is comparable to that obtained by the manometric apparatus.