Yet researchers have also found that after accounting for blacks’ lower average parental incomes and wealth levels, the black-white employment and earnings gaps nearly disappear, and, according to the book “Being Black, Living in the Red: Race, Wealth, and Social Policy in America,” blacks in fact tend to graduate high school at higher rates than whites.

Reconciling these findings is difficult, but it seems safe to estimate that for college applicants, poverty is a larger disadvantage than race. Affirmative action, therefore, undercompensates for economic disadvantage and overcompensates for racial disadvantage, at least when considering educational opportunities.

Racial preferences also entail steep and unique costs.

They stigmatize minorities. “26% of whites and 37% of blacks say that most people attribute minorities’ successes in business and education to racial preferences, rather than their own skills and abilities,” the Pew Research Center found. Racism is surely behind some doubt of minorities’ achievements, but it is tragic that excessive racial preferences, by lowering admissions standards for minorities, provide rationalization for such doubts, which then are used as evidence that the preferences are still necessary.

Based on last semester’s controversy on affirmative action, many will dispute that racial preferences involve “lowering admissions standards” for minorities.

Some say that racial preferences simply take into account the disadvantage overcome by minority applicants. But the research cited above shows that most of that disadvantage is economic, not racial, and that racial preferences currently overcompensate for racial educational disadvantage. Furthermore, most minorities benefitting from racial preferences are not particularly economically disadvantaged.

Others say that an applicant’s minority status is itself a contribution to the Harvard community. True enough, but no one is responsible for being a certain race. Excessive race preferences, therefore, lower the bar of what applicants must accomplish by themselves to gain admittance, like any excessive preferences do.

Still others argue that standardized tests are racially biased, a claim challenged by the College Board.  It is unlikely, however, that such bias would be significant enough to merit the magnitude of today’s racial preferences, since white students scored, on average, 100 points higher than their black counterparts.