Population dynamics and drought: A village in Niger

Summary The paper reports the results of demographic research in a rural village of about 1500 Hausaspeaking farmers in southern Niger, during the winter of 1973-74. The research site lies at the heart of the Sahel-sudanic zone just to the south of the Sahara, where drought, and in some areas, famine have exacted a heavy human, animal, and economic toll since 1968. The study was designed to measure and explain the change in the size and structure of the population during the years 1969-73. Social anthropological field techniques were used to ensure full and accurate reporting by community residents on all census topics. Data on rainfall and crop yields, on health and sanitary conditions, and on the political economy, social organization, and culture of the village were gathered in order to interpret the demographic situation The analysis of this data yields the following conclusions: 1. The population of the village appears younger (mean age: 15 years) and growing faster (mean doubling time: 23 years) than reported for Niger as a whole in 1972. 2. Contrary to what the researchers expected, the crude death rate, while relatively high to begin with, actually declined during the drought period (mean: 14.81); the crude birth rate remained very high (mean: 46.01), and the crude rate of increase rose from 1969 to 1973. 3. There was virtually no family out-migration from the target village during the drought, although the number of adult males participating in seasonal migrations to large West African towns rose from 35 per cent in 1969-70 to 75 per cent in 1973-74. 4. Problems of food production and distribution were acute, but thanks to the availability of donated foods, these were sufficiently short-lived during this drought cycle to make no discernible impact on population, although prolonged protein/calorie malnutrition among the very young may affect future fecundity.     

Combinatorial analysis for route first-cluster second vehicle routing

Two Route first-cluster second vehicle routing algorithms are contrasted in the first section of the paper. Next, the ‘large’ number of feasible solutions to a multiple travelling salesman problem is established given that each salesman can visit any number of customers in a stated range. An approximate expression is given for the ‘small’ fraction of this solution space searched by a route first-cluster second vehicle routing heuristic. Nevertheless, this heuristic is seen to be a very efficient means of searching its solution space.     

Comparing products using data envelopment analysis

Using an application of linear programming known as Data Envelopment Analysis (DEA), a method is described to compare products which vary in excellence along a number of dimensions, and for each of which there might be a number of associated “costs”. The method is illustrated by comparing published benchmarks of 37 computer printers. Potential uses of a DEA analysis of products might be: to assist corporate buyers who may need to reconcile a diversity of present and future uses in one standardised purchase; in competitor analysis; in determining unexplored market niches; and as a normative model of product excellence against which product purchasing behaviour could be compared.     

Inventory control in hospital blood banks

The delicate relationship between donors and the Transfusion Service in the U.K. implies a clear duty to make the best possible use of the limited blood supplies, and this turns attention upon the stocking policies adopted by Hospital Blood Banks. Whereas Blood Bank staff can obtain an intuitive grasp of the effects of various stock levels for the common bloods, this is not usually the case for the rare bloods which are more difficult to control. A policy decision has to be made which balances the conflicting stock requirements of maintaining a high availability and also low out-dating rates. A Markovian structure is exploited in this paper for this purpose and the effects of the key variables are shown to be interrelated. In any particular instance the form of the probability distribution of demand between replenishments, the scale of the throughput, the blood life in relation to the ordering interval, the fraction of blood transfused and the fraction of the replenishment order which is supplied to the Bank will together determine the form of the operating characteristics.