	Introduction

In recent years, there has been significant congressional interest in compensation of the federal workforce. The increased interest has been driven at least in part by the federal fiscal situation and in part by the state of the economy since the recession began in 2007. Issues related to the compensation of federal employees often center on the pay differential between federal workers and their private sector counterparts. For years, the annual President's Pay Agent (PPA) study, which is covered in greater detail later in this report, has shown a large wage penalty for federal workers compared to private sector workers in similar occupations. A spate of recent studies, which use a different analytical approach and data sources, has partially contradicted the findings of the PPA study by concluding that at least some federal workers enjoy a wage premium over comparable private sector workers. These studies and accompanying reporting on the comparison of compensation of federal workers to private sector workers provide an indication of the disparate findings, which makes it difficult to determine how compensation of federal employees actually compares to that of workers in the private sector. In evaluating claims about federal pay, there appear to be two basic approaches to comparing compensation in the federal and private-sector workforces—the human capital approach and the jobs analysis approach. These two approaches are not mutually exclusive but may be difficult to combine given data limitations. Each approach is outlined below, followed by an examination of a few recent studies comparing federal and private sector compensation. The studies reviewed were chosen because they are official government studies (President's Pay Agent, Congressional Budget Office) or have received significant attention in policy debates. The Human Capital Approach

The "human capital" approach attempts to account for (control) as many observable characteristics of individual workers as possible that are known to affect individual compensation. In this approach, an attempt is made to match comparable jobs in different sectors rather than comparable workers in those sectors. Of the five studies under review, one reports an overall average wage penalty for federal workers (PPA), one reports neither an overall average wage premium nor a penalty for federal workers (CBO), and three (Heritage, AEI, and Cato) find overall average wage premia for federal workers compared to private sector workers. Only two of the studies—CBO and AEI—report earnings differentials by level of educational attainment, however. While the AEI report shows a clear wage premium across levels of educational attainment, the more methodologically rigorous CBO study finds a more nuanced outcome. That is, federal workers with less than a bachelor's degree have on average a wage premium compared to private sector counterparts, while federal workers with post-graduate educational attainment experience a wage penalty relative to private sector counterparts. Results from these studies provide useful information. The range of worker and job characteristics is sufficiently broad across sectors that claims about "average" workers generally conceal much of the variation driving differences in compensation. For purposes of policy, the most informative studies show variation in compensation differentials by some control variables, particularly by some measure of human capital (e.g., education) or detailed occupation.
Recently there has been significant congressional interest in compensation of the federal civilian workforce. The increased interest has been driven at least in part by budgetary pressure and in part by the state of the economy since the recession began in 2007. Issues related to the compensation of federal employees often center on the pay differential between federal workers and their private sector counterparts. For several years, the annual President's Pay Agent (PPA) study has shown a large wage penalty for federal workers compared to private sector workers in similar occupations. A few recent studies, however, which use a different analytical approach and data sources, have partially contradicted the findings of the PPA study by concluding that at least some federal workers enjoy a wage premium over comparable private sector workers. These disparate findings make it difficult to determine how compensation of federal employees compares to workers in the private sector.
In evaluating claims about federal pay, there appear to be two basic approaches to comparing compensation in the federal and private-sector workforces—the human capital approach and the jobs analysis approach. The human capital approach attempts to account for as many observable characteristics of individual workers as possible (e.g., education, experience) that are known to affect individual compensation. The jobs analysis approach, on the other hand, focuses on matching comparable jobs in different sectors rather than workers with similar demographic characteristics in those sectors. These two approaches are not mutually exclusive but may be difficult to combine given data limitations. Each approach is outlined in this report, followed by an examination of a few recent studies comparing federal and private sector compensation. The studies reviewed were chosen because they are official government studies (President's Pay Agent, Congressional Budget Office) or have received significant attention in policy debates.
Results from these studies, which at times arrive at vastly different conclusions, provide some useful information about evaluating competing claims related to the compensation of the federal workforce. In general, the more methodologically rigorous "human capital" studies show a pay premium for federal workers with lower levels of educational attainment and a pay penalty for federal workers with higher levels of educational attainment. The range of worker and job characteristics is sufficiently broad across sectors that claims about "average" workers conceal much of the variation driving differences in compensation. For purposes of policy, the most informative studies show variation in compensation differentials by some control variables.
Of the five studies under review, one reports an overall average wage penalty for federal workers (PPA), one reports neither an overall average wage premium nor a penalty for federal workers, and three find overall average wage premia for federal workers compared to private sector workers. Only two of the studies—CBO and the American Enterprise Institute (AEI)—report earnings differentials by level of educational attainment, however. While the AEI report shows a clear wage premium across levels of educational attainment, the more methodologically rigorous CBO study finds a more nuanced outcome. That is, federal workers with less than a bachelor's degree have on average a wage premium compared to private sector counterparts, while federal workers with post-graduate educational attainment on average experience a wage penalty relative to private sector counterparts.