Adjusting Corruption Perception Index Scores for National Wealth

My post two weeks ago discussed Transparency International’s newly-released 2017 Corruption Perceptions Index (CPI), focusing in particular on an old hobby-horse of mine: the hazards of trying to draw substantive conclusions from year-to-year changes in any individual country’s CPI score. Today I want to continue to discuss the 2017 CPI, with attention to a different issue: the relationship between a country’s wealth and its CPI score. It’s no secret that these variables are highly correlated. Indeed, per capita GDP remains the single strongest predictor of a country’s perceived corruption level, leading some critics to suggest that the CPI doesn’t really measure perceived corruption so much as it measures wealth—penalizing poor countries by portraying them as more corrupt, when in fact their corruption may be due more to their poverty than to deficiencies in their cultures, policies, and institutions.

This criticism isn’t entirely fair. Per capita income is a strong predictor of CPI scores, but they’re far from perfectly correlated. Furthermore, even if it’s true that worse (perceived) corruption is in large measure a product of worse economic conditions, that doesn’t mean there’s a problem with the CPI as such, any more than a measure of infant mortality is flawed because it is highly correlated with per capita income. (And of course because corruption may worsen economic outcomes, the correlation between wealth and CPI scores may be a partial reflection of corruption’s impact, though I doubt there are many who think that this relationship is so strong that the causal arrow runs predominantly from corruption to national wealth rather than from national wealth to perceived corruption.)

Yet the critics do have a point: When we look at the CPI results table, we see a lot of very rich countries clustered at the top, and a lot of very poor countries clustered at the bottom. That’s fine for some purposes, but we might also be interested in seeing which countries have notably higher or lower levels of perceived corruption than we would expect, given their per capita incomes. As a crude first cut at looking into this, I merged the 2017 CPI data table with data from the World Bank on 2016 purchasing-power-adjusted per capita GDP. After dropping the countries that appeared in one dataset but not the other, I had a 167 countries. I then ran a simple regression using CPI as the outcome variable and the natural log of per capita GDP as the sole explanatory variable. (I used the natural log partly to reduce the influence of extreme income outliers, and partly on the logic that the impact of GDP on perceived corruption likely declines at very high levels of income. But I admit it’s something of an arbitrary choice and I encourage others who are interested to play around with the data using alternative functional forms and specifications.)

This single variable, ln per capita GDP, explained about half of the total variance in the data (for stats nerds, the R2 value was about 0.51), meaning that while ln per capita GDP is a very powerful explanatory variable, there’s a lot of variation in the CPI that it doesn’t explain. The more interesting question, to my mind, concerns the countries that notably outperform or underperform the CPI score that one would predict given national wealth. To look into this, I simply ranked the 167 countries in my data by the size of the residuals from the simple regression described above. Here are some of the things that I found: Continue reading

London Anticorruption Summit–Country Commitment Scorecard, Part 2

This post is the second half of my attempt to summarize the commitments (or lack thereof) in the country statements of the 41 countries that attended last week’s London Anticorruption Summit, in four areas highlighted by the Summit’s final Communique:

  1. Increasing access to information on the true beneficial owners of companies, and possibly other legal entities, perhaps through central registers;
  2. Increasing transparency in public procurement;
  3. Strengthening the independence and capacity of national audit institutions, and publicizing audit results (and, more generally, increasing fiscal transparency in other ways); and
  4. Encouraging whistleblowers, strengthening their protection from various forms or retaliation, and developing systems to ensure that law enforcement takes prompt action in response to whistleblower complaints.

These are not the only subjects covered by the Communique and discussed in the country statements. (Other topics include improving asset recovery mechanisms, facilitating more international cooperation and information sharing, joining new initiatives to fight corruption in sports, improving transparency in the extractive sector through initiatives like the Extractive Industries Transparency Initiative, additional measures to fight tax evasion, and several others.) I chose these four partly because they seemed to me of particular importance, and partly because the Communique’s discussion of these four areas seemed particularly focused on prompting substantive legal changes, rather than general improvements in existing mechanisms.

Plenty of others have already provided useful comprehensive assessments of what the country commitments did and did not achieve. My hope is that presenting the results of the rather tedious exercise of going through each country statement one by one for the language on these four issues, and presenting the results in summary form, will be helpful to others out there who want to try to get a sense of how the individual country commitments do or don’t match up against the recommendations in the Communique. My last post covered Afghanistan–Malta; today’s post covers the remaining country statements, Mexico–United States: Continue reading