Doyle, Orla; Harmon, Colm; Walker, Ian - 2005
particularly concerned with the extent to which their finding that income effects on child health are the result of spurious … estimates of the effect of parental education will be biased upwards. Moreover, it is very common for parental income data to be … grouped, in which case income is measured with error and the coefficient on income will be biased towards zero and there are …