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Showing papers on "Empirical research published in 1973"


Book
01 Jan 1973
TL;DR: Cross-cultural studies are necessary for the complete development of theories in environmental research as discussed by the authors since no one culture contains all environmental conditions that can affect human behavior, and no one country contains all possible types of man-made changes of the physical environment, nor all of the manmade adaptations to natural conditions such as climate, noise, air quality and potential hazards.
Abstract: Cross-cultural studies are necessary for the complete development of theories in environmental research since no one culture contains all environmental conditions that can affect human behavior. Likewise, no one country contains all possible types of man-made changes of the physical environment, nor all of the man-made adaptations to natural conditions such as climate, noise, air quality, and potential hazards. In addition, many places in which environmental researchers might be asked to work are in parts of the world where “development” is seen as a necessity or at least a desideratum. These places are often in countries where empirical research is not a well-established entity, hence the necessity for importing advisers from other countries. Although frequently forgotten (Fahvar & Milton, 1972), environmental assessments prepared by such advisers should include analyses of how a development project will affect a culture and even the behavior of people for whom the project was designed.

1,716 citations


Journal ArticleDOI
TL;DR: In this paper, the authors report the results of a study concerning the determination of factors which are associated with the success or failure of management information system (MIS) development projects.
Abstract: The authors report the results of a study concerning the determination of factors which are associated with the success or failure of management information system (MIS) development projects. The opinions of MIS professionals are compared with factors identified in an empirical study of twenty MIS projects in ten business firms.

263 citations



Journal ArticleDOI
TL;DR: A review of the literature dealing with the effects of communicating behavioral objectives to students can be found in this paper, where over twenty-five empirical investigations are reviewed in detail, and the context of the issue within instructional theory is discussed, as well as the rationales which predict a facilitative effect on learning.
Abstract: : The purpose of the paper was to review the literature dealing with the effects of communicating behavioral objectives to students. Over twenty-five empirical investigations are reviewed in detail. The first category of studies analyzed involved those investigations which addressed the general issue as to whether providing advanced knowledge of behavioral objectives to students facilitates their learning. A second group of studies sought an interaction between the availability of objectives and type of learning. A third group of studies sought interactions between the availability of objectives and learner characteristics. Finally, a fourth group of studies investigated the effect of the availability of objectives on the time required to complete the learning task. In the concluding section of the review, the context of the issue within instructional theory is discussed, as well as the rationales which predict a facilitative effect on learning. (Author)

121 citations


Journal ArticleDOI
TL;DR: In this paper, the authors evaluated whether price would act as a communicator of quality in a shopping situation more realistic than the experimental situations previously used, and to attempt to shed light on the reasons con
Abstract: It has been widely believed that price communicates quality to consumers. Examples of products for which pricing strategies reflect this belief include perfume [25], coffee [25], stockings [19], and whiskey [31]. Many studies [2, 14, 20, 21, 23, 24, 27, 34] have provided empirical support for the proposition that price communicates quality. These studies, however, were of limited scope and generally presented the subjects with an unrealistic experimental situation. This study had two purposes: to determine whether price would act as a communicator of quality in a shopping situation more realistic than the experimental situations previously used, and to attempt to shed light on the reasons con

108 citations


Journal ArticleDOI
TL;DR: In this article, the authors examined the performance characteristics of a group of companies by examining both operating and market-related characteristics, and compared them with other groups within the framework of the capital asset pricing model.
Abstract: THE PERFORMANCE of conglomerate corporations continues to be of interest to the financial community. Empirical research, however, remains somewhat limited. Studies by Reid (2) and by Weston and Mansinghka (8) have focused on operating performance characteristics of conglomerates. Reid concluded that firms stressing conglomerate diversification were "size-maximizers" which produced only a "serendipitous profitability performance." On the other hand, Weston and Mansinghka contend that conglomerates actually performed quite well since they were able to improve their operating profitability from depressed positions to "average earnings performance" levels. Some empirical evidence relating to market performance characteristics of conglomerates also exists. This evidence is based on research conducted within the framework of the capital asset pricing model. Smith and Schreiner (4) attempted to measure the "potential efficiency of conglomerate diversification" on an ex ante basis through the employment of a simulation technique. Mutual funds were found, on the average, to have higher levels of "diversification efficiency." Westerfield (7), in a response to the Smith and Schreiner study, also focused on conglomerate diversification by employing a measure of the correlation between the return on an individual security and the return on the market. He found some indication that conglomerates were able to reduce unsystematic risk (i.e., risk not attributable to the market) although conglomerates were not as completely diversified as mutual funds.' This paper attempts to provide additional insight into the performance of conglomerate firms by examining both operating and market-related characteristics. Samples of conglomerate and non-conglomerate firms are compared on the basis of operating profitability and traditional market-related characteristics, as well as within the framework of the capital asset pricing model.

104 citations



Journal ArticleDOI
TL;DR: In this article, the relationships between modes of communication, the communication environment and organizational structure are investigated, and a framework is presented within which the above relationships can be identified and studied.
Abstract: This paper is concerned with the relationships between modes of communication, the communication environment and organizational structure. This is a very neglected area of organizational analysis, which is surprising considering the possible implications of such relationships. A framework is presented within which the above relationships can be identified and studied. Field research methodology is essential to the effort and is discussed in some detail, along with the associated problems of measure and measurement of organizational communications behaviour and organizational structure. An empirical study is described, and some initial propositions tested. Distance appears to be a dominant factor in the mode of communication chosen, and it strongly influences the association of formal structural relations with modes of communication. Such conclusions are tentative, however, as we are describing an on-going research effort.

99 citations



Journal ArticleDOI
TL;DR: In this article, the authors examined the relationship between industry price-cost margins and diversification and found that diversification has a systematic influence on price cost margins which may be attributable to certain barriers to entry.
Abstract: U NFORTUNATELY, economic theory and existing empirical evidence provide little insight into the effects of diversification on industry performance. This is partially due to the fact that most previous empirical studies of diversification have been concerned with tabulating the extent of,1 or motives for,2 diversification. In order for the antiitrust authorities to develop a rational policy toward conglomerate mergers, it will be necessary to determine the competitive consequences of diversification. This study attempts to provide some empirical evidence on the effects of diversification by examining the relationship between industry price-cost margins and diversification.3 Specifically, the study examines the general proposition that diversification is an element of industry structure and the more narrow hypothesis that diversification raises barriers to entry into an industry. The study is based on a sample of 241 four-digit manufacturing industries from the 1963 Census of Manufactures. The primary testing technique is multivariate regression analysis. Results of the analysis provide tentative support for the proposition 'that diversification has a systematic influence on price-cost margins which may be attributable to certain barriers to entry.

93 citations



Book ChapterDOI
01 Jan 1973
TL;DR: This chapter discusses the role of notation-related imagery in mathematical problem solving and explores the extent to which visual imagery penetrates into the structure of the problem solving process.
Abstract: Publisher Summary This chapter discusses the role of notation-related imagery in mathematical problem solving. It explores the extent to which visual imagery penetrates into the structure of the problem solving process. The chapter presents work that is a mixture of subjective and objective methodologies. It discusses eight small empirical studies that constitute a tentative and incomplete exploration into the role of visual imagery in solving elementary mathematical problems. The investigation began with a protocol study in which people were asked to report on their use of visual imagery in the solution of elementary mathematical problems. Study 2 proved the striking spatial integration of image with stimulus reported by subjects in Study 1. Studies 3 and 4 were concerned with the temporal duration of images, Studies 5 and 6 with the relation of generated images to memory for specific visual formats, and Studies 7 and 8 with further spatial properties of generated images.

Journal ArticleDOI
TL;DR: A review of the literature upon which this chapter is based led to several conclusions as discussed by the authors, namely, that the literature is basically atheoretical in nature, it contains little work designed to develop and test theories describing the dynamics of the change process or explaining why organizations like schools vary in the degree and speed with which they change.
Abstract: tions exist because authors emphasize different aspects of the literature. It is the quantity of empirical work and speculative papers that attracts the attention of some reviewers, not its quality. As research designed to test hypotheses derived from theory about organizational change, the quality is poor, and little is contributed to systematic understanding of organizational change in schools. The review of the literature upon which this chapter is based led to several conclusions. The literature is basically atheoretical in nature. It contains little work designed to develop and test theories describing the dynamics of the change process or explaining why organizations like schools vary in the degree and speed with which they change. Moreover, confidence is not warranted in a number of currently held generalizations about organizational change because the research methods and statistics upon which they are based are inadequate. Most empirical reports reviewed were atheoretical efforts to make changes, not efforts to test theories of change. The absence of critical attention to the methodological and statistical procedures used in these studies reflects this emphasis on precipitating change rather than studying it. The extension of knowledge about organizational change will require empirical studies of greater theoretical, methodological, and statistical sophistication. Effective CHARLES E. BIDWELL, University of Chicago, was the editorial consultant for this chapter. ' The author wishes to acknowledge his appreciation to Charles Bidwell for constructive criticisms of earlier drafts of his paper and his deep gratitude to Neal Gross and Marilyn Bernstein. Many of the ideas presented here originated from work with them, and some are contained in a recent book (Gross, Giacquinta, & Bernstein, 1971). He alone, however, is responsible for the shortcomings of the paper.

Journal Article
TL;DR: Pavitt et al. as discussed by the authors identified the factors influencing the process of technological innovation by analysing the results of empirical research on the subject undertaken over the past ten years in the member countries of the OECD.
Abstract: The report written in four parts, by Keith Pavitt, with the assistance of Salomon Wald, attempts to identify the factors influencing the process of technological innovation by analysing the results of empirical research on the subject undertaken over the past ten years in the member countries of the OECD. The report's analysis is concentrated on technological innovation rather than on diffusion, for want of empirical information on the later.


Posted Content
TL;DR: This article showed that the perceived risk of the borrowing firm tends to be negatively influenced by the aggregation of financial reports only when the financial situation of that firm is marginal. But they did not examine the utility of using more detailed data.
Abstract: This paper reports on an empirical study concerning the stipulation that detailed financial information is more useful for lending decision making. Prior research and other evidence assert that the utility of more detailed data is greater than the utility of (condensed) aggregated data. Since the utility of using data cannot be evaluated in a direct manner, decision effects have been used as a surrogate measure. The primary result of this research shows that the perceived risk of the borrowing firm tends to be negatively influenced by the aggregation of financial reports only when the financial situation of that firm is marginal. This result, then, supports imputing a higher utility for detailed data, but only under certain conditions. A secondary result casts doubts on the strength of the predictive ability of financial ratios if not accompanied by financial information more detailed than that used in computing these ratios.

Book ChapterDOI
TL;DR: In the history of demand analysis, two threads, related but separable, can be discerned as mentioned in this paper : the work of economists interested in the discovery of general laws governing the operation of markets, particularly agricultural markets; and the work by originally statisticians, interested in psychological laws governing what has come to be called consumer preference.
Abstract: In the history of demand analysis two threads, related but separable, can be discerned. These are first the work of economists interested in the discovery of general laws governing the operation of markets, particularly agricultural markets; and second the work of those, originally statisticians, interested in the psychological laws governing what has come to be called consumer preference. This dichotomy continues to characterise the subject. As computing opportunities and skills have expanded, empirical research has produced more sophisticated demand equations while, at the same time, theoretical economists and mathematicians have enormously increased our knowledge of the pure mathematics of preference relations. While these two activities have not always been in balance, the great strength of empirical demand analysis has been the existence of strong theoretical foundations which could be drawn upon or modified as practice demanded. This interplay between the theory and reality has been perhaps more fruitful in this than in any other branch of economics.

Journal ArticleDOI
TL;DR: This article showed that the perceived risk of the borrowing firm tends to be negatively influenced by the aggregation of financial reports only when the financial situation of that firm is marginal. But they did not examine the utility of using more detailed data.
Abstract: This paper reports on an empirical study concerning the stipulation that detailed financial information is more useful for lending decision making. Prior research and other evidence assert that the utility of more detailed data is greater than the utility of (condensed) aggregated data. Since the utility of using data cannot be evaluated in a direct manner, decision effects have been used as a surrogate measure. The primary result of this research shows that the perceived risk of the borrowing firm tends to be negatively influenced by the aggregation of financial reports only when the financial situation of that firm is marginal. This result, then, supports imputing a higher utility for detailed data, but only under certain conditions. A secondary result casts doubts on the strength of the predictive ability of financial ratios if not accompanied by financial information more detailed than that used in computing these ratios.



Journal ArticleDOI
TL;DR: Two theoretical models have emerged to account for variations in the response to imprisonment among inmate populations as discussed by the authors, the "deprivation model" focuses attention on the pressures and deprivat...
Abstract: Two theoretical models have emerged to account for variations in the response to imprisonment among inmate populations. One, the “deprivation model,” focuses attention on the pressures and deprivat...


Journal ArticleDOI
TL;DR: In this paper, the authors identify and explain the phases and stages of the development of small social systems in the context of psychotherapy and training groups, including sensitivity training, sensitivity groups, psychotherapy groups, college classrooms, and natural groups.
Abstract: Small group researchers and participant observers of psychotherapy and training groups have for some time attempted to identify and explain the &dquo;phases&dquo; or &dquo;stages&dquo; which characterize the development of small social systems. To this end, many different kinds of groups have been studied-laboratory groups, sensitivity training groups, psychotherapy groups, college classrooms, and &dquo;natural&dquo; groups in &dquo;real life&dquo; settings. In addition, several generations of social scientists have struggled with the complexities of social change in a wide variety of collectivities. One perennial goal of at least

Journal ArticleDOI
TL;DR: The author concludes that a great deal more empirical information needs to be gathered on the behavior of the participants in the health-care sector and on the technical constraints under which that sector operates before one can confidently develop and follow a coherent blueprint for a reorganization of the American health- Care system.
Abstract: Students of the American health-care delivery system are generally agreed that, under its present organization, the system will be unable to accommodate any of the more ambitious national health-insurance schemes now before Congress It is argued that the current system is actually a fragmented "nonsystem" that fails to deliver the right mix of care to the right people and at the right time As a result, it is argued, the health-maintenance services received by the average American tend to be of dubious overall quality and are unnecessarily costly To eliminate these shortcomings, a great number of reforms have been proposed, the bulk of which, however, fall into one of the following major types: (a) a shift away from the fee-for-service mode of paying for health services and toward prepayment of comprehensive health care, (b) the substitution of paramedical for medical manpower and of capital for all types of manpower, (c) the consolidation of small provider facilities (especially solo medical practices) into larger production units, and (d) the integration of provider facilities in centrally directed regional systems In this essay, the various reform proposals that have been proposed at one time or another are explored against the backdrop of pertinent empirical research available at this time This exploration leads to the disappointing conclusion that far too many of the proposed reorganization schemesparticularly the much touted idea of a nationwide network of presumably competitive Health Maintenance Organizations-appear to have been proffered more on the basis of intuition or faith than on the basis of convincing empirical evidence At the risk of appearing timid and of exasperating the impatient reformer, the author concludes that a great deal more empirical information needs to be gathered on the behavior of the participants in the health-care sector and on the technical constraints under which that sector operates before one can confidently develop and follow a coherent blueprint for a reorganization of the American health-care system

Journal ArticleDOI
TL;DR: In this article, the authors make use of data prepared for a comprehensive study on the Israeli kibbutz economy, which is currently in preparation at the Falk Institute for Economic Research in Israel, and financed by the Falk institute and the Twentieth Century Fund.
Abstract: T is an accepted proposition that there is a positive association between efficiency and experience in production. Yet, until quite recently, only industrial engineers tried to estimate and evaluate the contribution of experience to productivity, while economists have on the whole neglected this aspect of production. The growing interest in growth and the search for factors which can help to explain quantitatively the growth of production over and above the growth of the conventionally identified inputs have led economists to reconsider the problem. Arrow's pioneering article on the subject suggested that "learning," which may be identified with cumulated experience, contributes to the growth of productivity.' In contrast to the engineer's approach, which usually concentrates on the effect of experience on efficiency in specific processes, the economist's approach is more general. Learning is not exclusively attributed to the individuals who make up a firm's labor force or to specific processes, though both are considered to be integral elements of the process. Rather, it is ascribed to the production unit as a multidimensional entity. It is therefore the modus operandi of the firm in each of its many facets entrepreneurial ability, technical expertise, the know-how of its labor force, layout, buying and selling, human relations, lines of command, all of them subject to continuous change which is the best testing ground of the empirical significance of the learning hypothesis. Since the acquisition of experience requires time, time or a proxy for it, such as cumulated investment and cumulated output, must obviously appear as an explicit variable in an empirical test of the hypothesis. Productionfunction analysis based on time series is therefore an obvious way of studying the quantitative effect of learning. Arrow's reference to the Swedish Horndal firm is a case in point.2 However, it is only rarely possible to find a similar example. This means that although empirical testing of the learning hypothesis can be carried out on the basis of time-series data,3 it strains the theoretical framework of the analysis. The use of cross-section data in estimating the contribution of experience to productivity is therefore an obvious alternative. Since the input and output figures necessarily refer to different firms, this way of tackling the problem is also constrained by the necessity of assuming that, except for random differences, the technologies applied by the firms concerned are identical. The requirement of intra-firm technological identity, or to put it more mildly, the similarityof-technology condition, can, in practice, be approximated under certain conditions. For example, a good approximation to the identical technology constraint can be obtained within a narrowly defined branch and for a group of firms located in a relatively small area, which maintain strong personal contact between managements so as to facilitate the inter-firm flow of information and whose labor forces are similar in background, attitude, and know-how. If the firms in such a group differ in their acquired "experiences," and if these differences can be easily measured in terms of simple units, such a group may be a satisfactory testing ground for the learning hypothesis. These conditions obtain in the case of kibbutzim in Israel. They form a tightly organized group of collectives, relatively homogeneous in manpower, which has established effiReceived for publication December 6, 1971. Revision accepted for publication July 10, 1972. * This article makes use of data prepared for a comprehensive study on the Israeli kibbutz economy currently in preparation at the Falk Institute for Economic Research in Israel, and financed by the Falk Institute and the Twentieth Century Fund. The authors are indebted to Yoram Levin for his help in the preparation of the quantitative skeleton of this article. 1See Kenneth J. Arrow (1962), pp. 155-174. 2Production methods in this firm do not appear to have changed for about 15 years; productivity, however, increased continuously. 'Shifts in the production function cannot be ruled out if the period studied is long. For shorter periods, for which this objection may have less force, the number of observations may be too small to allow for statistically significant results.

Journal ArticleDOI
TL;DR: A survey of 52 empirical studies of welfare recipients is presented in this paper, where the authors compare empirical evidence with the assumptions of current welfare reform proposals and conclude that there is a large gap between policy assumptions and research findings, concluding with suggestions for both.
Abstract: In the following article, 52 empirical studies of welfare recipients are surveyed. The object of the survey is to compare empirical evidence with the assumptions of current welfare reform proposals. Discovering a large gap between policy assumptions and research findings, the survey concludes with suggestions for both. Following the lead of their fellow taxpayers, social scientists have devoted increasing amounts of time and effort to the study of poverty and dependency; discussions of marginal tax rates, motivation, work incentives, and general welfare reform are now common in the journals of sociology and economics. Despite this extensive and growing interest in these problems, relatively little in the way of hard data has appeared in professional journals; most discussions continue to reflect the casual empiricism and bias of the authors. While one might conclude from this state of affairs that little empirical work has been done, this is not the case. On the contrary, federal agencies, especially the Manpower Administration of the U.S. Department of Labor, have funded a large number of research projects which bear directly on these issues. The results of these projects and other studies provide considerable insight into the dynamics of impoverishment and the potential of public assistance programs. Unfortunately, the limited exposure of these studies has made their results inaccessible to all but a handfull of social scientists. This brief survey attempts to help close the communications gap. In the following section, the results of 52 empirical studies are surThe author is Assistant Professor of Economics, University of Maryland. * Support for this study was received from the U.S. Department of Labor; all opinions are those of the author. An earlier version of this paper, entitled "Facts and Fictions of Welfare Reform," was released by the Department of Labor. The Journal of Human Resources * VIII * Supplement This content downloaded from 157.55.39.60 on Mon, 18 Jul 2016 04:11:05 UTC All use subject to http://about.jstor.org/terms 20 1 THE JOURNAL OF HUMAN RESOURCES veyed. For organizational and analytical purposes, these results are discussed in the context of welfare reform. In particular, I first attempt to identify the major assumptions of current and pending welfare reform (for example, the Work Incentive Program [WIN], the Talmadge Amendments, President Nixon's reform bill [H.R. 1], and Senator Long's proposed Guaranteed Job Opportunity Program) and then subject these assumptions to empirical scrutiny.' THE ASSUMPTIONS OF REFORM A. The Distinction Between Working and Nonworking Poor At the core of much welfare reform is the persistent distinction between "working" poor and "nonworking" poor. President Nixon's proposal (H.R. 1) is the most explicit in this regard, actually creating separate programs (OFP and FAP) to serve each target population. Senator Long's bill includes the same categorizations, while the present system of Aid to Families with Dependent Children (AFDC) explicitly excludes poor families headed by working fathers [40].2 The distinction drawn is based on the assumption that a poor person's employment status is stable over a considerable period of time. Unfortunately, there is little empirical justification for such a categorization. On the contrary, numerous studies and even official program statistics indicate that (1) there is a high degree of mobility between employment and dependency status, and (2) simultaneous work and welfare status is common. With regard to status mobility, AFDC program statistics [52] indicate that the median time on welfare is only 20 months. Longitudinal and retrospective studies of these recipients show that both before and after receiving public assistance, families are in the labor force [11, 22, 30, 32, 37, 46]. Similarly, studies of the working poor have demonstrated that substantial numbers (estimates run over 25 percent) of poor persons now working re1 It should be noted at the outset that the studies synthesized here are remarkably consistent in their findings and of generally high research quality. Hence, the usual caveats about the tentativeness of conclusions are omitted; only in a few places have I found it necessary to point out that available evidence is scarce. 2 The AFDC program is the existing mechanism for public assistance to families with children (currently about 11 million recipients), while the AFDC-U program serves families with unemployed fathers (approximately 660,000 recipients). The WIN program is the adjunct manpower training program for adult AFDC and AFDC-U recipients. The Talmadge Amendments (effective July 1, 1972) expand the WIN program and increase related work requirments. H.R. 1 is the Nixon Administration's (revised) welfare reform package, which would extend aid to the working poor. For more detail see [38, 48]. This content downloaded from 157.55.39.60 on Mon, 18 Jul 2016 04:11:05 UTC All use subject to http://about.jstor.org/terms

Journal ArticleDOI
TL;DR: Recent developments in the applications of mathematical programming techniques to problems encountered in educational planning are examined in terms of recent developments in socio-economic and public sector planning and the emerging major research needs in educational policy planning.
Abstract: The specific aim of this article is to examine recent developments in the applications of mathematical programming techniques to problems encountered in educational planning. Applications are given for selected problems at national, state, regional and local levels of planning and the implications of this work for educational research methodology is noted. Special attention is given to applications at the microanalytic or school district level, since most applications in this domain are of recent origin and have been developed in disciplines other than education, e.g. industrial engineering, econometrics, public administration, business and operations research. Applications are discussed in light of their relationship to theoretical and empirical research on educational production functions. The final section contains some directions and implications for future research which are discussed in terms of recent developments in socio-economic and public sector planning and the emerging major research needs in educational policy planning.

Journal ArticleDOI
TL;DR: In this article, empirical Bayes procedures are tied in with current work in mental test theory and point estimators of "true scores" are derived for the binomial and Rasch test models.
Abstract: In this paper, recent developments in empirical Bayes procedures are tied in with current work in mental test theory. Point estimators of “true scores” are derived for the binomial and Rasch test models. These estimators are shown to be asymptotically optimal. Smoothing and an empirical study of the behavior of empirical Bayes estimates are taken up in the final section.


Journal Article
TL;DR: In this article, the authors present a model that presents MODAL SELECTION in a DIFFERENT, not-generally-looked-at MANNER, and they hope that through this model TRAFFIC MANAGERS will gain a better understanding of the decision process.
Abstract: THIS MODEL PRESENTS MODAL SELECTION IN A DIFFERENT, NOT-GENERALLY-LOOKED-AT MANNER. THE DECISION PROCESS IS NOT AS EASY, NOR AS COLDLY OBJECTIVE AN ONE MAY BE LED TO BELIEVE. TRANSPORT MEDIA ARE CHOSEN ON THE BASIS OF MORE THAN RATE OR SERVICE DIFFERENCES. IN FACT, THE LEAST TOTAL COST SOLUTION MAY NOT BE USED. IT IS HOPED THAT, THROUGH THIS MODEL TRAFFIC MANAGERS WILL GAIN A BETTER UNDERSTANDING OF THE DECISION PROCESS. BY RECOGNIZING THIS, OBJECTIVE DATA MAY NOT BE OVERSHADOWED BY PERSONAL BIAS OR VAGARY. THUS DILIGENT RATE ANALYSES OR SOPHISTICATED SIMULATIONS WILL MAKE A STRONGER CONTRIBUTION TO THE SELECTION PROCEDURE. THIS IS NOT TO SAY THAT SUBJECTIVE JUDGMENTS WILL OR SHOULD BE ELIMINATED. BUT THESE JUDGMENTS SHOULD BE BASED UPON THE RESULTS OF AN INFORMATION SEARCH OF ALL POSSIBLE ALTERNATIVES, NOT UPON A LIMITED SET OF ALTERNATIVES, NOR UPON PERSONAL BIAS. FOR THE MODEL ITSELF, ADDITIONAL EMPIRICAL STUDIES SHOULD BE CARRIED OUT. WITH FURTHER STUDY, THE CONTENT AND STRUCTURE OF THE MODEL CAN BE DEFINED. THEN TESTING OF VARIOUS HYPOTHESES CAN BEGIN. HOPEFULLY THE END RESULT WILL BE A VIABLE AID TO THE DECISION PROCESS OF TRAFFIC MANAGERS.