Showing papers in "Journal of the Royal Statistical Society in 1961"

The world’s hunger and future needs in food supplies

Abstract: Part of the world's population is hungry (undernourished) and malnourished. The paper presents a method of estimating the incidence of hunger in the population, based on the international reference scale for calorie requirements and on the variation in energy expenditure among men of the reference age group; illustrates the application of the method on calorie intake distributions available for a few countries; and estimates that between 300 and 500 million people in the world are undernourished. The paper also presents data on calorie consumption levels, region by region, together with the corresponding requirements, and draws attention to the hunger gap of 11 per cent. between the average levels of per caput consumption and requirement for the populous region of the Far East, and to the wide variation in calorie consumption levels between countries and between segments of the population within countries against a relatively small variation in their calorie requirements. Evidence on the extent of malnutrition is also presented together with an estimate of its incidence relative to the nutritional standards enjoyed by well-developed countries. The paper concludes that between one-third and one-half of the world's population suffers from hunger and malnutrition. As a background to this analysis the paper examines the scope, limitations and sources of errors in available data on food consumption and requirements. In Part Ii the paper gives an estimate of the amount of foods needed for the world's growing population to eliminate the hunger gap and to ensure a moderately good quality of diet for the people of the world. It uses the approach of linear programming in the calculation of the needed food supplies, by ensuring that the additional food supplies, while meeting the nutritional targets, cost the least to the consumer, are feasible of achievement within a reasonable period of years and are capable of being absorbed by the people. It concludes that the total supplies of cereals in the Far East would have to be more than doubled, and those of animal products increased to six times their present size, in order to ensure a reasonably adequate level of nutrition to its people by the year 2000. For the world as a whole the broad conclusion is that, should population grow according to the United Nations' medium forecast, the food supplies would have to be more than doubled by 1980 and tripled by the turn of the century in order to bring about a moderate improvement in the level of nutrition of the people of the world.

Delays on a Two-lane Road

Abstract: SUMMARY A theoretical formula is found for the average speed achieved over a long journey by a vehicle travelling along a road according to certain rules governing overtaking, when the other traffic on the road is postulated to be of a particularly simple kind. Except for the vehicle whose behaviour is studied, vehicles in each direction travel at the same speed, and are spaced at random, but with a certain minimum distance between vehicles. The vehicle being studied wishes to travel faster than the other vehicles; when it overtakes, it must pass the whole of a bunch of vehicles at minimum spacing in a single manoeuvre. It overtakes without delay if there is a sufficient gap in the opposing traffic. If delay occurs, then a greater gap in the opposing traffic is required, to allow for time lost in accelerating. An alternative application of the theory is to one half of a dual carriageway, in which the two traffic lanes are occupied by vehicles travelling at two different speeds. A curious feature of the results is that when the traffic flows increase beyond a certain level, appreciably below the theoretical capacity of the road, the fast vehicle cannot maintain a higher average speed than that of the other vehicles: the whole time is spent waiting for opportunities to overtake, and the average wait per overtaking becomes infinite. Numerical values of the average speed have been tabulated using an electronic computer. Standard values of all the constants of the model were selected for two-way and one-way roads separately, and these constants were then varied two, three or four at a time. Two general conclusions are indicated by the numerical results. Firstly, more acceleration, obtained at the expense of reduced maximum speed (and perhaps greater fuel consumption) by lowering the top gear ratio, would probably provide increased mean journey speeds for most modern cars under typical traffic cQnditions. Secondly, the cutting of safety margins and clearances when overtaking would not normally provide any worthwhile increase in mean journey speed.