| dc.description.abstract | The paper analyzes the impact of sensor readings of dry grain mass yield of wheat, barley and rapeseed on combine speed during harvesting on three plots. The combine was fitted with site-specific yield monitoring sensors. This paper displays detailed tables of statistical procedure carried out for wheat in the analysis of combine speed, whereas final results for barley and rapeseed are itemized. After harvest, the three plots were divided into three groups each according to yield levels: low, medium and high, respectively. On the rapeseed plot, the Kruskal-Wallis H test did not reveal statistically significant difference in combine speed between the plot zones that belong to different yield-level groups, chi(2)(2, N = 2187) = 4,570, p = 0,102. On the basis of mean values for group ranks, the highest combine speed on wheat and barley plots has been found in the medium-yield-level group. Therefore, subsequent analysis of differences was conducted between the groups using Mann-Whitney U test. Combine speed during wheat harvest did not differ significantly in the low- and high-yield-level zones of the plot, Z = -1,213 and N = 3453, p = 0,225, while comparison between speeds within the medium-yield-level group to the other two groups exhibited statistically significant difference, effect size being approx. 0,1. During barley harvest, combine speeds differ statistically significantly when all three groups are compared for low and high impact according to Cohen's criterion based on effect size. | en |
