Competitive bidding — The probability of winning

A company bidding by sealed tender needs to know the relationship between their bid price and their chances of winning the contract. Previously published models for computing the probability of winning are examined and found to be inaccurate. The problem is reformulated, and a new general predictive model for computing the probability of winning is developed. The method of computation is illustrated by a simple worked example.     

Preprocessing the 1960–1970 U. S. census public use samples

This is a report on computer programming undertaken to preprocess the 1960–1970 U. S. census public use samples to increase their accessibility. This includes wholesale recoding into positive integers from 1 to N, with 0 reserved for “not applicable”, combining household and person records, sorting records into ten 1/10,000 samples, compacting binary codes to fit on a single reel of tape, and the production of a revised set of formatted tapes.     

Number and mean age of acceptors and users as related to programme duration

Abstract A decline in annual acceptances in a contraceptive programme is open to multiple interpretation. The decline may reflect an adverse change of attitudes and therefore a lowered disposition to accept the method among couples of the population generally. Alternatively, if the population has an irregular age distribution, the decline may mean only that the numbers of couples of prime contraceptive age have temporarily dropped. Thirdly, if the rate of previous acceptance has been high, the main cause of a slackening in new acceptances may simply be that previous acceptances have partially depleted the pool of eligible couples. Fewer eligible couples are left than previously as a consequence of past acceptance, removing couples interested in contraception faster than the family-building process can create new ones.     

A computer model of family building based on expected values

A computerized probability model of family building is described. Called FERMOD, the model is designed to follow the changing distribution of children ever born and birth intervals of a large homogeneous population as it moves through the reproductive period. Use of the model presupposes assumptions about such factors as risks of fetal wastage, lengths of pregnancy, and postdelivery amenorrhea conditional to outcome of pregnancy, length of reproductive period, fecundability, desired family size, preferred birth spacing!, and effectiveness of contraception. Use of FERMOD is illustrated in a limited application to United States fertility. Relations to other models are briefly discussed.     

Productivity of highly skilled immigrants: economists in the postwar period

Prior work finds declining immigrant quality in the postwar period that is linked to source-country and skill-composition changes associated with the 1965 Immigration Act. This paper uses a unique panel of foreign- and native-born American Economic Association members to show that the highly skilled experienced a similar shift away from European migrants toward those from Asia. However, the findings do not indicate that this change in source-country composition has been accompanied by a decline in quality; rather, the most recent cohorts of foreign-born economists appear to be more productive than their native counterparts.     

Rolling with the shakes: an insight into teenagers’ perceptions of recovery after the Canterbury earthquakes

Natural disasters are harmful worldwide events that inflict multiple psychosocial impacts on disaster-exposed individuals. A significant proportion of affected individuals are teenagers (13–18 years old) who, compared with adults, have been historically overlooked in disaster research. The literature is particularly sparse concerning teenagers’ recovery from natural disasters, specifically what recovery means to them and the contributing factors towards their positive recovery. Therefore, the aim of the current study was to gain deeper insight into this largely unexplored area by conducting five focus groups with teenagers (16–18 years) who experienced at least one of the Canterbury, New Zealand, earthquakes since and including the initial September 2010 earthquake. This study directly asked teenagers about their recovery over the three years after the initial earthquakes, with data being analysed using thematic analysis. Two main themes were identified: (1) perceptions of recovery, with three sub-themes (i) knowledge and being less frightened, (ii) talking about the earthquakes and (iii) shift in perspectives; and (2) contributing factors to recovery, with three sub-themes (i) participation in the community response, (ii) returning to school and (iii) the rebuild of Christchurch. These factors provide insight into how we can better support the recovery process for disaster-exposed teenagers to reduce long-term distress.     

A common-features analysis of Amsterdam and London financial markets during the eighteenth century

We examine the financial linkage between the London and Amsterdam financial markets using stock prices recorded in each market over the period 1723-94 in conjunction with tests for common trends, cycles, and regime shifts. These tests reveal a surprising degree of integration between the markets as their prices move together in both the short and long run. Moreover, shocks to the assets translate quickly and accurately between markets. It also appears that Dutch investment did not destabilize London markets and stock prices in London were the primary determinant of prices in Amsterdam.     

Improving homeless persons' utilisation of primary care: lessons to be learned from an outreach programme in The Netherlands

Elissen AMJ, Van Raak AJA, Derckx EWCC, Vrijhoef HJM. Improving homeless persons' utilisation of primary care: lessons to be learned from an outreach programme in The Netherlands Faced with rising homelessness, countries around the world are in need of innovative approaches to caring for those without shelter, who, more often than not, suffer from severe health problems. We conducted a case study of an innovative Dutch Primary Care for the Homeless (PCH) programme to gain insight into clients' demographic characteristics, health problems and service use, and to develop an explanation for its success in increasing the latter. Our analyses are based on a combination of quantitative and qualitative data. The results of the study suggest that the success of the PCH programme can be explained by the providers' pragmatism and will to adapt their mode of care provision to the behavioural patterns and needs of their homeless clients.     

Family planning and fecundity

Abstract A computerized probability model of family-building, FERMOD, is described and then utilized in an investigation of relations between family planning and fecundity as applying to white couples of the contemporary United States. Models of this type that formulate reproductive performance as a stochastic process permit one to explore relations that are not directly observable and in this manner to secure at least partial answers to questions not subject to investigation by survey research alone. Two main questions are addressed concerning the dependence of family planning success upon fecundity: (1) How quickly does spacing control deteriorate when natural fecundability is taken at progressively lower values or when the risk of pregnancy wastage is set at progressively higher values? (2) What is the distribution of unsought births among couples of average fecundity when they practise contraception with specified effectiveness and have stipulated spacing and family size goals?