Since recent immigrants tend to earn less than natives, their relative earnings have been adversely affected by an increase in the return to labor market skills over the past three decades. Using longitudinal Social Security records matched to cross-sections of the SIPP and CPS, I estimate the return to skills rose by 41% between 1980 and 1997. This reduced the relative earnings of immigrants who arrived in the 1980s and early 1990s by 10 to 15 percentage points. Examining solely the earnings of recent immigrants may lead to an overly pessimistic picture of their actual labor market skills.

Multiple proxy variables are typically available for an unobserved explanatory variable in a regression. We provide a procedure by which the coefficient of interest can be estimated from a regression in which all the proxies are included simultaneously. This estimator is superior in large samples to the common practice of creating a summary measure of the proxy variables. We examine the relationship between parents' income and children's reading test scores in the United States, and between parents' assets and children's school enrollment in India, and demonstrate that the reduction in attenuation bias from a better use of proxy variables can be significant.