KANSAS WHEAT YIELD RISK MEASURES AND AGGREGATION - A METAANALYSIS APPROACH

A meta-analysis approach to prediction of farm level yield risk from c ounty level yield series is applied to Kansas wheat yields. A nonlinea r relationship between county level and farm level yield risk is found , which indicates that yield risk increases at an increasing rate as t he number of acres in the risk measure decreases. County level yield v ariability should be adjusted upward by approximately. 1% for each per cent difference in county acreage and average farm acreage within the county. The meta-analysis approach is shown to be promising for the pr ediction of farm level yield risk when farm level information is diffi cult to obtain.