Bell Curve

140 Cognitive Chses and Social Behavior Poverty 141The role of the mother's socioeconomic background indetermining which white children are poorProbability of being in poverty asparental SES goes from low to high70% -50% - White mother.7 who are separated,divorced, or never married20% - Married white mothersVery lowVery high(-2 SDs)Parental SES(+2 SDg)Note: For computing the plot, age and 1Q were set at their mean valtres.chance of being below the poverty line, far ahove the usual level forwhites and far ahove the level facing a woman of average socioeconomicbackground but superior IQ. We cannot even be sure that higher socioeconomicbackground reduces the poverty rate at all for unmarriedwomen after the contribution of 1Q has been extracted; the downwardslope of the line plotted in the graph does not approach statistical signifi~ance."~'There are few clearer arguments for bringing cognitive ability intothe analysis of social problems. Consider the hundreds of articles writtenabout poverty among children and about the effects of single-parentfamilies on poverty. Of course, these are important factors: Childrenare more often poor than adults. Family breakup is responsible for a majorportion of the increase in child poverty. But if analysts are trying tounderstand the high rates of poverty among children, it must be doneagainst the background that whatever other factors increase the risk ofpoverty among unmarried mothers, they hit unmarried mothers at lowlevels of intelligence much harder than they do those at high levels ofintelligence--even after socioeconomic background is held constant.HOLDING BOTH COMPLICATIONS AND POLICY THOUGHTSAT BAYYou have been following a common process in social science. An initiallysimple issue becomes successively more complicated. And we havebarely gotten started-an analysis in a technical journal seldom has asfew independent variables as the ones we have examined. For that matter,even this simplified analysis represents only the end result of a longprocess. In the attached note, we describe how big the rest of the icebergis.lUlComplex analysis has both merits and faults. The merit is that thecomplications are part of reality. Einstein's injunction that solutionsshould be as simple as possible, but no simpler, still applies. At the sametime, social science often seems more in need of the inverse injunction,to introduce as much complexity as necessary, but no more. Complicationscan make us forget what we were trying to understand in the firstplace. Here is where we believe the situation stands:By complicating the picture, we raise additional questions: Educationis important in affecting poverty; the appropriate next step is to explorehow intelligence and socioeconomic status are related to years of education.Marriage is important in determining poverty; we should explorehow ~ntelligence and socioeconomic status are related to marriage.These things we shall do in subsequent chapters.But the simple picture, with only IQ, parental SES, and age in theequation, restricted to our all-white sample, continues to tell a story ofits own. A major theme in the public dialogue in the United States hasbeen that socioeconomic disadvantage is the primary driving force behindpoverty. The simple picture shows that it just isn't so forThe high rates of poverty that afflict certain segments of the white populationare determined more by intelligence than by socioeconomicbackground. The force and relevance of this statement does not seemto us diminished by the complications it does not embrace.Indeed, now that we are returning to basics, let us remember somethingelse that could be overlooked in the welter of regression analyses.The poverty rate for whites in Class V was 30 percent-a percentageusually associated with poverty in poor urban neighborhoods. Ethnically