Modes, weighted modes, and calibrated modes: evidence of clustering using modality tests
应用统计学的模态检验方法，检验全球劳动生产率分布的多模态性，发现无论是否加权，多模态现象在1960-2000年间普遍存在，并探讨了经济体在模态集群间的移动及发展因素与多模态的关系。
Abstract We apply recent results from the statistics literature to test for multimodality of worldwide distributions of several (unweighted and population‐weighted) measures of labor productivity. Specifically, we employ Silverman (Bump) and Dip modality tests, calibrated to correct for their incorrect asymptotic levels. We show that test results are sensitive to the test statistic employed and to population weighting. But regardless of the statistical criterion used, multimodality is present throughout, or emerges during, our sample period (1960–2000). We also examine (a) movements of economies between modal clusters and (b) relationships between certain key development factors and multimodality of the productivity distribution. Copyright © 2008 John Wiley & Sons, Ltd.