英文文献：How Are Crop Yields Distributed?-作物产量如何分布?比较六种流行的作物产量分布，以确定哪一种最能描述样本外的产量波动
英文文献作者：Norwood, F. Bailey,Roberts, Matthew C.,Lusk, Jayson L.
英文文献摘要：
Six popular crop yield distributions are compared to determine which best describes yield fluctuations out-of-sample. For 183 crop and county combinations, each distribution is estimated and ranked according to its log-likelihood function observed at out-of-sample observations. A semiparametric model dominates the contest for most crops and counties, likely due to its flexibility and treatment of heteroskedasticity. Most other models ranked lower because their variance equation performed poorly out-of-sample.

对于183种作物和县组合，根据样本外观察到的对数似然函数对每种分布进行估计和排序。半参数模型在大多数作物和县之间的竞争中占优势，这可能是由于它的灵活性和对异方差的处理。大多数其他模型排名较低，因为它们的方差方程在样本外表现不佳。