The stickiness of class

Much has been written about income mobility in recent years, generally implying that there is a considerable mobility between generations. These studies do not jibe well with my experience of social mobility. This book review in the Economist addresses this disconnect, arguing that class is very sticky and class mobility is very low even over a large number of generations. Long time frames are always difficult to relate to personal experience but you can get a sense of the argument from your own extended family. There is considerable income variation within my family, covering more than half of the income percentile range, from a pastor of a small rural congregation up to an oil company executive. Yet, they all belong to the same middle class social group. If you look at the children in the next generation, outcomes and parental income do not co-assort. All of the pastor's children attained four year degrees from decent universities as did the oil executive's children. The prospective incomes of this next generation are largely unaffected by the previous generation's income. No one accumulated sufficient wealth to permanently move their lineage into the upper class nor did anyone fall into a permanent underclass.

Individual incomes are a noisy signal displaying considerable variation from generation to generation. This noise largely reflects individual choices whereas class, although much harder to define, is quite stable over long generational time frames. The fortunes of individuals within the family rise and fall, but the fortunes of the family remain relatively stable, based on long established class attributes. The review addresses what this means for social policy, concluding that some mechanisms to promote social mobility are a good idea if we wish to avoid both permanent underclasses and overclasses.