Recent decrease of cereals production per capita in the world shown by analysis with the empirical bayes smoothing method
1998
Yanagimoto, M. (National Food Research Inst., Tsukuba, Ibaraki (Japan)) | Yanagimoto, T.
In order to pursue recent characteristics in cereals production in the world, the trend of cereals production in the world and also in 13 selected countries was analyzed. Data for amount of cereals production, yield, area and population were cited from FAO Production Yearbook (1975-1995). The main statistical method employed was the empirical Bayes smoothing method. Results obtained are summarized as follows: 1) the amount of cereals production per capita in the world has started to decline in recent years. The turning point is estimated to be 1985. 2) This trend was discussed in terms of four indices, areas, area per capita, yield and yield/population. 3) A sharp decrease of production amount per capita was observed in other cereals, but not in the three major cereals, wheat, rice and maize. However, a clear increase was not observed in any specific cereal. 4) In the last 20 years, an increase in the amount of cereals production per capita was observed in the three largest countries by population including China. On the other hand, the same trend was not observed in the three largest countries by food production including the USA. 5) The increase of yield can be expected to cover the sharp increase in population, but the increase of areas can not be expected to. Therefore, the yearly trend of the ratio of yield/population is useful for following the trend of the amount of cereals production per capita in a practical way
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