全球貪腐傳染之空間分析：以世界銀行貪腐控制指數為例

Analysis on Global Corruption Contagion: A Case Study of the Control of Corruption

過去少數針對全球貪腐傳染的研究已經發現，在控制其他相關因素下，某個國家或地區的貪腐程度會與鄰近地區的貪腐程度呈現正相關。然而，目前並未有任何研究針對全球貪腐傳染可能的所在區域進行探索。因此，本研究根據貪腐具有傳染性的假定出發，利用空間統計進行經驗性的分析。使用global Moran's I與Getis-Ord's local Gi*針對世界銀行（World Bank）全球治理指標（world governance indicators,WGI）中貪腐控制指數（control of corruption），進行空間自相關分析（熱點分析），比較不同年度中世界各國貪腐現象群聚的分布狀態與變化趨勢。研究結果顯示，貪腐現象在亞洲與非洲確實產生範圍擴張且群聚增強的傳染現象。在亞洲，近十幾年來貪腐傳染擴散的範園，僅有小幅度的擴張。反之，非洲則慢慢開始傳染蔓延到北非與西非各國。至於強度方面，無論亞洲或非洲皆有貪腐群聚強度增強的總體趨勢。其次，在針對廉潔的群聚區域分析則發現，其擴散蔓延的現象在歐洲與北美洲並不明顯，甚至有群眾範圍縮小的趨勢。但是，大洋洲的澳洲與紐西蘭則形成另一個顯著的群眾。至於，廉潔群眾強度的變化是較小的。歐洲的捷克、英國與北美洲的加拿大、美國都有廉潔群聚強度轉弱的趨勢。反觀大洋洲的澳洲與紐西蘭，群眾強度則為漸增的情況。

A small literature confirms the contagious effect of corruption, and finds that a lower national level of corruption is associated with a lower regional measure of corruption, as measured by the average level of corruption in one country’s neighbors. This study assumes that corruption is contagious, and uses the spatial statistics to carry out an empirical analysis. Using the spatial autocorrelation methodologies, including global Moran’s I and Getis-Ord’s local Gi*, this study maps and compares spatial clusters for the control of corruption index form World Bank’s global governance indicators (World Governance Indicators, WGI) in different year. The results show that the corruption is indeed having significant contagion and strong cluster in Asia and Africa. The scope of corruption cluster in Asia only expands a little during the last decade. However, the corruption cluster is slowing beginning to spread to North and West African. In general, the strength of corruption cluster in Asian and Africa is getting higher. Secondly, corruption well-control cluster is found not obvious spreading in Europe and North America, even cluster is getting narrow. However, Australia and New Zealand form another significant integrity cluster. Although the strength of integrity cluster is changing little, the strength of integrity cluster in Czech Republic, the United Kingdom, Canada, and the United States is decreasing a little. On the contrary, the strength of integrity cluster in Australia and New Zealand are increasing.