Determinants Of The Level And Volatility Of Blackcurrant Purchase Prices In Poland

The aim of the study was to identify the factors which significantly influence the purchase prices of blackcurrants in Poland. The average annual purchase prices of blackcurrants between 2004 and 2021 were the research material. The study was based on the data published by the Institute of Agricultural and Food Economics – National Research Institute in the semi-annual journal “Fruit and Vegetable Market”. The relationship between the fruit purchase prices and the selected explanatory variables was analysed with the multiple regression method. Single-equation econometric models were designated as multifactor functions. The reference publications were used as the basis for the selection of the following set of potential variables explaining the purchase prices of blackcurrants: the area of blackcurrant plantations in Poland, the yields of blackcurrants in Poland, the yields of blackcurrants in Ukraine, the yields of blackcurrants in Germany (the main importer of frozen products and a producer of currants), the volume of frozen blackcurrant exports and the export price of frozen blackcurrants. Apart from that, the qualitative variable COVID-19 was created, which allowed for the greater demand for blackcurrant preserves during the pandemic. In order to determine the factors which significantly influenced the purchase prices of blackcurrants during the period under analysis, the all possible regression method, also known as the best subsets regression, available in the Statistica PL package, was applied. This was a model with two explanatory variables: the export price of frozen blackcurrants and COVID-19. The linear determination coefficient of the estimated econometric model indicated that 90% of the variance of blackcurrant purchase prices was explained by the model.