№ 160(6), June, 2020
Public date: 30.06.2020
Archive of journal: Articles count 15, 43 kb
-
PROBABILITY-STATISTICAL MODELS OF CORRELATION AND REGRESSION
08.00.13 Mathematical and instrumental methods of Economics
DescriptionThe correlation and determination coefficients are widely used in statistical data analysis. According to measurement theory, Pearson's linear paired correlation coefficient is applicable to variables measured on an interval scale. It cannot be used in the analysis of ordinal data. The nonparametric Spearman and Kendall rank coefficients estimate the relationship of ordinal variables. The critical value when testing the significance of the difference of the correlation coefficient from 0 depends on the sample size. Therefore, using the Chaddock Scale is incorrect. When using a passive experiment, the correlation coefficients are reasonably used for prediction, but not for control. To obtain probabilistic-statistical models intended for control, an active experiment is required. The effect of outliers on the Pearson correlation coefficient is very large. With an increase in the number of analyzed sets of predictors, the maximum of the corresponding correlation coefficients — indicators of approximation quality noticeably increases (the effect of “inflation” of the correlation coefficient). Four main regression analysis models are considered. Models of the least squares method with a determinate independent variable are distinguished. The distribution of deviations is arbitrary, however, to obtain the limit distributions of parameter estimates and regression dependences, we assume that the conditions of the central limit theorem are satisfied. The second type of model is based on a sample of random vectors. The dependence is nonparametric, the distribution of the two-dimensional vector is arbitrary. The estimation of the variance of an independent variable can be discussed only in the model based on a sample of random vectors, as well as the determination coefficient as a quality criterion for the model. Time series smoothing is discussed. Methods of restoring dependencies in spaces of a general nature are considered. It is shown that the limiting distribution of the natural estimate of the dimensionality of the model is geometric, and the construction of an informative subset of features encounters the effect of "inflation coefficient correlation". Various approaches to the regression analysis of interval data are discussed. Analysis of the variety of regression analysis models leads to the conclusion that there is no single “standard model”
-
05.13.18 Mathematical modeling, numerical methods and software complexes
DescriptionThe article presents ways to estimate the socio-economic condition of the subjects of the Russian Federation using fuzzy production systems, discriminant analysis and neural networks. This study is based on the thirteen indicators of the socio-economic condition of the regions of the Russian Federation identified by RIA Rating rating agency. The goal of the work is to develop a software package combining the estimation methods above and allowing to get three alternative estimation options for a subject of the Russian Federation, using these thirteen indicators. The developed program assigns each region an estimation from the following set: AAA– the highest socio-economic condition, AA - very high, A– high, BBB– above average, BB– average, B– below average, CCC– low, CC– very low, C– the lowest indicators of the socio-economic conditions in the region of the Russian Federation. The software package is developed in Matlab and has an intuitive interface. The results can be used as an alternative to current methods of estimation of the socio-economic indicators
-
PRODUCTIVITY OF SUGAR CORN DEPENDING ON NITROGEN FERTILIZERS
06.01.01 General agriculture, crop production (agricultural sciences)
DescriptionThe article gives a review of the results of studying the features of the formation of sugar corn grain yield depending on the application of nitrogen mineral fertilizers used for sowing and fertilizing. The object of research was the mid-early hybrid of corn called Krasnodarsky Sakharny 280 SV (FAO 280). In the experiment, 2 factors were studied: factor Ā - sowing nitrogen fertilizer (b / ud (k), 15 and 30 kg.d.v. / ha), factor B - root nitrogen fertilizing (b / ud (k), 15 and 30 kg.dv./ha). The total area of the plot is 20 m2, the accounting area is 10 m2. The number of rows in the plot is only 4, including accounting - 2. The plots are systematically placed. In the fall, the main mineral fertilizer was applied at a dose of N30P60K60, under the main tillage - plowing to a depth of 25-27 cm. Four-fold repetition. The predecessor is winter wheat. The counts and observations in the experiment were carried out according to generally accepted methods. Studies have established that the highest yield of ears of sugar corn in milk ripeness - 14.60 and 14.71 t / ha, respectively, was obtained on options with the addition of N30 when sowing + N15 or N30 in root dressing. A further increase in the dosage of nitrogen to 60 kg.d.v./ha does not lead to an increase in yield. The highest level of profitability was obtained with the option of sowing nitrogen fertilizer at a dose of 30 kg.d.v / ha in combination with nitrogen for top dressing at a dose of 15 kg.d.v / ha (N30 + N15)
-
EFFECTIVENESS OF USING MULTIKAN-6 WHEN GROWING YOUNG FOXES
DescriptionThe cost-effectiveness of animal husbandry in the conditions of Yakutia causes irreparable damage to viral diseases, such as salmonellosis, viral hepatitis, parvovirus enteritis and others. Based on this, in animal husbandry, increased attention is paid to the prevention of viral diseases. The work was carried out in the period from 2009 to 2012. in the conditions of LLC "Pokrovskoye animal husbandry" of the Khangalassky ulus of the Sakha Republic (Yakutia). Boning of young animals showed that all his indicators were higher for pups born in 2011. So body size and physique are rated higher by 15.15%, in males - by 20.58%. Hair color was better in females by 19.44%, in males by 22.66%. As a result, the classiness of the animals of the experimental groups was higher than that of pups born in 2010. The commodity properties of the animal products of experimental animals and its cost are consistent with the results of the valuation. The offset on the quality of the fur products of the experimental groups in 2011 was determined at 89.02%, which is higher than the 2010 results by 10.32%. The average cost of one fur of a silver-black fox in 2011 was 2225.62 rubles. Additional vaccination of the main herd of foxes in autumn against the viral diseases with the vaccine "Multikan-6" has a positive effect on the quality of the fur products. The economic effect amounted to 258.62 rubles per 1 skin of a silver-black fox (at 2020 prices)
-
05.20.01 Technologies and means of mechanization of agriculture (technical sciences)
DescriptionThe urgent task facing the agro-industrial complex is the improvement of storage methods for agricultural products and the development of new ones. One of the actively cultivated crops, characterized by a variety of species, valuable taste and medicinal properties – grape. It is possible to provide the population with fresh grapes of high quality through the introduction of effective storage technologies that reduce losses, preserve marketable properties and biological value. One of the effective ways to preserve the quality of grapes during storage is the use of sulfur dioxide (SO2). This gas inhibits oxidative enzymes in berries, thereby reducing the rate of development of the phytopathogen Botrýtis cinérea, which causes gray rot. At the same time, it is especially important to control the rate of release of sulfur dioxide, since at the beginning of storage it is necessary to ensure the receipt of a large amount of it, which will eliminate Botrytis spores present on the surface of the berries and stabilize the existing damage. Further, during the entire period of storage of grapes, sulfur dioxide must be supplied in minimal quantities. Such dynamics of SO2 emission can be ensured by the use of two-phase generators of sulfur dioxide. The article investigated the effects of sulfur dioxide generators on the quality of grapes during storage. The study also investigates quality indicators of grapes of several varieties zoned in the Krasnodar region under long-term storage