In this section, I document issues of instrument strength in three of the four papers described in Section 2.1.<sup>8</sup> I first replicate the benchmark empirical specifications of OBT, HOZ and CC, in the first columns of Tables 2, 3 and 4, respectively. OBT find a negative and significant estimate of the effect of net inequality on growth, and a small positive effect of redistribution on growth that is not significantly different from zero. They also reject the null hypothesis that these two slopes sum to zero, suggesting that redistributive policies that reduce the net Gini have a positive and statistically significant effect on growth. Their estimated negative growth effect of inequality is substantial. A one‐standard deviation increase in the net Gini (i.e. a 0.1 point increase in the Gini on a scale from zero to one, corresponding roughly to the rise in inequality in China over the past 20 years) would lower cumulative growth over the following five years by 0.07 (i.e. 0.07/5=0.014, or 1.4 percent per year), corresponding to just over one‐ half a standard deviation of per capita GDP growth rates in the benchmark regression sample.<sup>9</sup> In the case of HOZ, my replication is close to, but not exactly the same as the authors’ results. I begin with the specification in Column 4 of Table 3 of their paper, which regresses log per capita GDP on its lag, as well as lagged and twice‐lagged inequality, and a set of additional control variables. I make one correction and one change to this benchmark specification as estimated in the replication code provided by the authors. The correction involves including some instruments in the instrument set that were missing in the authors’ original code.<sup>10</sup> The change is that I drop the additional control variables 8 DKSRT kindly provided me with replication datasets and codes for the SYS‐GMM inequality and growth regressions in their paper. However, I do not include this paper in my replication for two reasons. First, their specification and dataset are very similar to that of OBT, which I do replicate below, and so the same concerns about weak instruments are likely to apply in DKSRT as well. Second, the replication codes provided by DKSRT implemented the SYS‐GMM estimator in a way that is inconsistent with the internal logic of this estimator. Specifically, the published regressions in DKSRT are implemented using the `xtdpdsys` command in Stata. In the replication code they provided to me, they used the following syntax: `xtdpdsys gdpgrowth log_gdp2005pc gini` . This formulation fails to recognize that the syntax of `xtdpdsys` treats variables listed immediately after the dependent variable as exogenous covariates, while predetermined regressors are listed subsequently using the `pre()` option. This implies that lagged income ( `log_gdp2005pc` ) and inequality ( `gini` ) are treated as strictly exogenous in the way that DKSRT used `xtdpdsys` . In the case of lagged income, this is inconsistent with the internal logic of the SYS‐GMM estimator. In the case of inequality, this assumes away any potential endogeneity problems for inequality which motivated the use of the SYS‐GMM estimator in the first place. This in turn implies that assessing internal instrument strength in their benchmark specification is not particularly meaningful, and so I do not pursue this further here.

9 Note that OBT have average annual growth over a five‐year period as the dependent variable in their specification. This means that the coefficients on inequality and redistribution in Table 2 are 5 times as large as the coefficients reported in OBT, which is just an inconsequential rescaling.

> 10 HOZ implement the SYS‐GMM estimator using `xtabond2` .  The syntax of `xtabond2` requires that all exogenous regressors be included in the variable list following `xtabond2` , and also in the `ivstyle()` instrument list since they serve as their own instruments (see Roodman (2009), page 124).  However, HOZ did not do this in their replication code for two sets of variables:  (i) the period dummies, which I include in the `ivstyle()` instrument list for both the levels and differenced equations as required by `xtabond2` syntax, and

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