William K. Hall

The business portfolio approach—Where it falls down in practice

Abstract During the past decade the SBU (or portfolio) concept has enjoyed widespread popularity as a basis for corporate-wide strategic planning systems within large, diversified firms. This article discusses the implementation of such systems on the basis of 3 years of clinical and small sample research. A ‘basic model’ of implementation is used as a basis for comparison to progressive practice as observed in a sample of 13 firms. Furthermore, a new conceptual perspective for the portfolio concept is developed as a complement to the observed approach to implementation.

Why Risk Analysis Isn't Working

Abstract In this article the author argues that despite its popularity among researchers and managers alike, Risk Analysis as a management tool has not been successful. He postulates that in the end managers will give up attempting to make formal analysis of risks, substituting more effective means of living with the ‘results’ of those risks as they arise.

The Application of Multifunction Stochastic Service Systems in Allocating Ambulances to an Urban Area

Alternative policies for the allocation and distribution of ambulances are studied for the city of Detroit, Michigan. Data on emergency occurrence and service processes were collected and analyzed, and these data analyses are utilized to model the ambulance system as a multifunction stochastic service system with semi-Markov arrivals and state-dependent server selection. Numerical results are developed predicting the performance of both single function recovery systems and dual function police-ambulance systems under alternative operating policies.

Management science approaches to the determination of urban ambulance requirements

This research paper summarizes a systematic approach to the determination of urban ambulance requirements. Quantitative measures of ambulance system performance and alternative system configurations were developed, and these were examined for the city of Detroit, Michigan. Sampling techniques and data analysis procedures were used to develop an analytical model of the Detroit emergency recovery system, and this model was then utilized to predict the performance of alternative system configurations under varying operating policies. Results and conclusions are presented for the specific system under consideration; extensions of these techniques to other urban emergency systems are also suggested. THE DEVELOPMENT of effective methods for transporting the victims of emergencies to a hospital is a major problem in contemporary society. Various studies have estimated that 18-20 per cent of the 50,000 annual traffic fatalities in the United States could be avoided with more adequate emergency medical services. Although comparable statistics are not available for medical emergencies (heart attacks, strokes, etc.) and other accidental injuries, it seems clear that the failure to provide rapid, effective care for these emergencies leads to increased morbidity and mortality for many victims. This paper reports on a study conducted in Detroit, Michigan to consider one aspect of the emergency medical care problem--the determination of the number and placement of ambulances necessary to provide adequate service in an urban area. Increasing the number of ambulances assigned to a service area and placing these vehicles closer to the sites of potential emergencies should reduce the system response time. This reduction will place an emergency victim into contact with appropriate medical care more rapidly, and this rapid care should reduce the extent of victim morbidity and mortality. Consequently it would appear that the effects of changing the number and placement of recovery vehicles (the recovery system configuration) can be evaluated in terms of changed victim mortality/morbidity indices, Unfortunately, two factors make such evaluation criteria inappropriate. First, victim morbidity/mortality is influenced by many factors in addition to the ambulance system configuration. The quality of ambulance attendant training and medical capability, the victims pre-emergency physical condition, the severity of the emergency and the quality of medical treatment in the hospital emergency room all influence the victims condition. Since the effects and interactions between these * This paper is based upon remarks prepared for the 1971 Systems Engineering Conference ofthe American

Changing perspectives on the capital investment process

Abstract The environment within which institutions undertake commercial and industrial activity changes both as a result of decisions dependent on the institution itself and as a result of decisions independent of the institution. In recent years many of these changes have resulted in changing perspectives on the range of criteria which should be considered when determining how and where large corporations should invest their money. This paper examines these changes in corporate practice and identifies the cumulative results of these changes in the environment of corporate activity. The paper also examines some of the key elements in new approaches which corporations are adopting to capital investment decisions by utilizing data on a broadly based research project which examines in depth the capital investment/ resource allocation processes of five large, worldwide, manufacturing firms. The subject is of vital importance to large and small businesses, both because of the crucial importance of investment decisions and because of the importance for future strategic planning of identifying the environment within which corporate activities take place.

The association of accident severity and frequency with vehicle age: A study in three Michigan counties for the period 1 January to 30 September, 1966

AN INVESTIGATION OF THE ASSOCIATION OF VEHICLE AGE WITH CRASH FREQUENCY AND SEVERITY IS PRESENTED.. SAMPLES OF VEHICLES INVOLVED IN CRASHES AND CONTROL SAMPLES FROM THE TOTAL VEHICLE POPULATIONS WERE SELECTED FROM THREE MICHIGAN COUNTIES. THE CRASH SAMPLES WERE CLASSIFIED INTO FATAL CRASHES, SEVERE INJURY CRASHES, AND MINOR CRASHES. STATISTICAL COMPARISONS AMONG THESE SAMPLES HAVE REVEALED THAT THE THREE POPULATIONS ARE NOT DISTRIBUTED DIFFERENTLY WITH RESPECT TO AGE. FURTHER COMPARISONS HAVE SHOWN THAT THE CRASH POPULATIONS AND CONTROL POPULATIONS ARE NOT DISTRIBUTED DIFFERENTLY WITH RESPECT TO AGE. THESE DATA AND ANALYSES FAIL TO SUPPORT EITHER THE NOTION THAT VEHICLES BECOME MORE SUSCEPTIBLE TO CRASHES AS THEY AGE, OR THE NOTION THAT THE LEVEL OF DAMAGE, GIVEN A CRASH OCCURS, INCREASES WITH VEHICLE AGE. /AUTHOR/

A Probabilistic framework for accident data analysis

ELEMENTARY CONCEPTS OF PROBABULITY THEORY ARE APPLIED TO INTRODUCE A FREMEWORK FOR THE ANALYSIS OF ACCIDENT DATA. THE PROBLEM OF DRAWING STATISTICAL INFERENCES WITHIN THIS FRAMEWORK IS DISCUSSED, AND ALTERNATIVE TECHNIQUES FOR MAKING SUCH INFERENCES ARE REVIEWED. A BRIEF SURVEY OF THE PROBLEMS INCURRED IN ANALYZING REAL DATA WITH THIS TECHNIQUE IS PRESENTED. /HSL/