Precision agriculture: temporal yield correlation of grid yield data from Henry County, Ohio over the past years 1995-1998

This study calculated Pearson correlations between yield grids from three fields in Henry County, Ohio over the years 1995-1998. Field 1 was 176 acres, Field 2 was 140 acres and Field 3 was 144 acres. Overall, the study found little correlation when comparing yields for a grid with yields from previous years for that grid. However, a greater level of statistically significant correlations emerges when the information set includes the yields for previous years for the grid and surrounding grids. This finding suggests that expanding the geographical area used to explain a grid's yield may increase the predictability of a grid's yield. However, even for the later analysis, the average absolute value of the correlations is 0.14. Thus, the previous yields explain only a small amount of the variation in yields within a field. Furthermore, all but one of the significant correlations are negative, implying that the current year's grid yield is inversely correlated with yields in previous years. Thus, grid yields tend to revert to the mean grid yield for the field. In conclusion, these results call into question the economic profitability of precision agriculture; although, it must be quickly added that this is an extremely small sample over only a few years. Thus, additional work is needed that broadens the areas studied and the length of time studied