METHODS OF INVESTIGATION INTO REGIONAL DIFFERENCES IN TOMATO CROPPING
Hence the management of the production process by the grower on his holding differs completely from the management of big industrial enterprises.
The big industrial companies for instance run their own research work and apply the results in their production schemes straightforward. The holding of the grower, however, is too small for this procedure and he has to rely upon the results gained elsewhere. This can be experience from other holdings (this is the function of a centre) or results obtained from experiments.
The industrial manager has no comparison for his production schedule with similar production schemes of other enterprises. The horticulturalist on the other hand has the disposal of data from many similar holdings. This situation enables him to detect differences in management with other holdings and to compare different regions.
For this type of investigation the statistical method known as "factor analysis" is most useful.
The aim of the research work dealt with in this paper was to discover regional and local differences in the production of tomatoes in heated and unheated glasshouses in The Netherlands. The items investigated were yields, revenues and some materials used in the production scheme.
From earlier investigations it has been shown that differences in gross-revenue per surface-unit were the main factor determining the different results of management (1). Therefore we have limited our investigations to factors responsible for differences in yields and revenues between different holdings and different regions.