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line to it. But any attempt to illustrate an abstract
argument by concrete data is better than speculating in
the void.
The most impressive feature of the data is the linear and
very regular character of the regression of income on
wealth. The regression coefficient is in most cases around
2/3 but it may be as low as 1/2. A considerable defect of
the data is the unequal size of the wealth (as well as the
income ) classes. The range of the classes increases with
the wealth.The last but one wealth class has a range about
four times as great as the lower wealth classes. This
makes it very difficult to decide whether the variance and
higher moments of income are independent of the size of
wealth. In the Swedish data the variance increases in the
higher wealth classes. This may,however, be plausibly
explained by the increase in the range of these classes.
The same defect mars the comparison of the conditional
distributions of income in the various wealth classes.
They all have a Pareto tail,but the Pareto coefficient is
markedly lower in the last two or three wealth classes
than in the others.This,again,may be plausibly explained
by the greater range of these high wealth size classes.