Is diversity our strength? Our leaders certainly seem to think so. And many multinational corporations are of the same mind. In a series of influential reports with cringeworthy titles like ‘Diversity Wins’, researchers at McKinsey have put forward the officious-sounding “business case for diversity”. In short, they claim that more ‘diverse’ management leads to better company performance.
As for proposed mechanisms, they list several: ‘diverse’ teams are more innovative, ‘diverse’ companies have a more positive global image, and employees in ‘diverse’ companies feel a greater sense of belonging.
The image below details some of their findings. Each chart is a comparison between firms in the bottom 25% and top 25% for executive ‘diversity’, with the outcome being the likelihood of financial outperformance (a measure of company performance). So for example, the 2014 report ‘Diversity Matters’ found that firms in the top 25% for executive ‘diversity’ were 35% more likely to achieve financial outperformance than those in the bottom 25%.
The McKinsey researchers measured ‘diversity’ using something called the Herfindahl–Hirschman index. This sounds very complicated, but it just means squaring the proportions of different racial groups in the company’s management, and then adding up the results. For example, if a company’s management was 70% white and 30% black, the index would be (0.7*0.7) + (0.3*0.3) = 0.58.
Enter Jeremiah Green and John Hand – two U.S. economists who tried to replicate McKinsey’s findings. In a new paper published in Econ Journal Watch, they summarise what they found.
To begin with, McKinsey would not provide Green and Hand with their data. Nor would they even share the names of the relevant firms. (This is obviously bad scientific practice on McKinsey’s part.) Hence the authors decided to focus on public U.S. companies in the S&P 500 – a sample that likely overlaps substantially with the one used by McKinsey. They also used data from the same pre-Covid time window.
What did the authors find? McKinsey’s “business case for diversity” is built on sand.
Their main finding is shown below. Each chart plots company performance from 2015–2019 on the y-axis against executive ‘diversity’ in 2020 on the x-axis. The left-hand chart uses eight racial categories to calculate diversity, while the right-hand chart uses five. In both cases, there is zero association between the two variables: companies with more executive ‘diversity’ do not perform better than those with less.
And as Green and Hand point out, there’s an additional problem with McKinsey’s argument. Even if company performance was associated with executive ‘diversity’, that wouldn’t prove the latter causes the former. After all, it could be the other around: perhaps companies that perform better can afford the luxury of greater executive diversity.
In a separate paper co-authored with Sekou Bermiss, the economists show that nine measures of executive ‘diversity’ do not predict any of six measures of company performance in the next financial year. So their null result appears to be very consistent.
Green and Hand have not conclusively falsified the claim that more ‘diverse’ management leads to better company performance; that would require studies that can get around the problem of reverse-causality mentioned above. Nonetheless, they have shown that evidence supporting the “business case for diversity” in fact does no such thing.
To join in with the discussion please make a donation to The Daily Sceptic.
Profanity and abuse will be removed and may lead to a permanent ban.