These arguments notwithstanding, we believe that a logical starting point is to hypothesize that nonprot compensation is determined in competitive labor markets.
Competition implies that the marginal worker will be indifferent between identical positions in nonprot and prot-seeking enterprises. In its absence, some jobs will
be rationed and some employers will pay more than needed to fulll their demand for labor. However, competitive markets need not require identical levels of pay.
As mentioned, wages may deviate if there are compensating differentials or if indi- viduals are willing to donate labor to nonprots. Therefore, we are particularly inter-
ested in considering the joint hypothesis of competitive labor markets and the ab- sence of labor donations. The testable prediction is that the nonprot wage
differential will be eliminated by including sufcient controls for worker and job characteristics.
III. Previous Research
Previous studies of nonprot compensation, summarized in Table 1, yield ambiguous results. Early examinations Johnston and Rudney 1987; Shackett
and Trapani 1987; Preston 1989 suggest a large nonprot wage penalty but are hampered by the lack of information on the type of employer, requiring the imputa-
tion of nonprot status.
Researchers focusing on narrowly dened industries obtain equivocal ndings. Weisbrod 1983 shows that public interest lawyers earn 20 percent less than those
in the private sector and believes this is due to heterogeneity in preferences, rather than in worker quality. However, using the same data, Goddeeris 1988 claims the
lower wages reect personal characteristics and that public interest attorneys earn no less than if employed by prot-seeking companies. Borjas, Frech III, and Gins-
burg 1983 argue that the relatively high pay observed in nonprot nursing homes represents rent-sharing due to attenuated property rights. Conversely, Holtmann and
Idson 1993 claim the wage premium occurs because nonprot nursing homes use higher quality labor and that registered nurses could actually earn more if they
switched to for-prot facilities. Preston 1988 shows that federally regulated non- prot day care centers pay 5 to 10 percent more than for-prot facilities and interprets
this as evidence of philanthropic wage-setting. However, she nds no differential for non-federally regulated centers. Mocan and Tekin forthcoming show that the
size of the nonprot premium in this industry varies considerably with the type of ownership, characteristics of the staff, and hours worked.
12
Leete’s 2001 examination of data from the 1990 Census indicates that the overall nonprot differential is eliminated by including detailed controls for industries and
occupations. Within three-digit industries, nonprot workers are as likely to obtain statistically signicant wage premiums as penalties. These conclusions need to be
interpreted with caution, however, because the controls for industries and occupa-
12. Roomkin and Weisbrod 1999 indicate that there is ambiguity even within industries. Focusing on six top managerial positions in hospitals, they nd lower nonpro t compensation in three chief executive
ofcer, chief operating ofcer, and top patient care executive but higher pay in three others chief nancial ofcer, top human resources executive, and head of nursing services.
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Table 1 Previous Research on Nonprot Earnings Differentials
Study Data
Results Comments
Borjas Frech III, and 1973–74 National Nursing
Nursing home workers in religious- Many results are statistically insig-
Ginsburg 1983 Home Survey
afliated nonprots earn 4 percent nicant or sensitive to the choice
less per hour than for-prot em- of specications.
ployees; those in other nonprots receive an insignicant 1.6 per-
cent premium. Some evidence of higher wages for homes with
more generous Medicaid reim- bursement programs.
DuMond 1997 1995 Current Population
Nonprot workers earn 6 percent Not clear how government workers
Survey Outgoing Rota- 11 percent less per hour than
are treated. Small number of tran- tion Groups
counterparts without with con- sitions between for-prot and non-
trols for industry and occupation. prot employment in wage-
Larger differential for males 19 change models.
percent than females 0 to 5 per- cent. Gaps shrink to an insigni-
cant 0 to 4 percent in rst-differ- ence models. Nonprot workers
have higher pensionhealth insur- ance coverage and lower displace-
ment rates.
R uhm
and B
orkoski
997 Frank 1996
Cornell Employment Sur- Nonprot differential in annual earn-
Small and unrepresentative sample vey and other sources.
ings was 259 percent for recent Cor- in main analysis; few controls.
nell graduates, controlling for sex, GPA, and college curriculum. Other
evidence of negative compensating differentials for working for socially
responsible employers.
Goddeeris 1988 Nationally representative
Public Interest lawyers PIL earn Sector denitions differ from Weis-
surveys of private and pub- 37 percent less than those in private
brod 1983. Selection identied by lic interest lawyers in
rms but this is entirely due to dif- community size, political activities
19734. ferences in characteristics. They
orientation. would earn no less if they switched
into the private sector. Holtmann and Idson
Registered nurses in 1985 Nonprots employ higher quality
No distinction between government 1993
National Nursing Home registered nurses. OLS models re-
and private nonprot nursing homes. Survey
veal a 3 percent hourly wage pre- Identication restrictions of selectiv-
mium in nonprot homes and ity-corrected models are question-
steeper experiencetenure proles for able.
them. However, selectivity-corrected models indicate that nurses in non-
prots actually earn less than they would if employed in for-prots.
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Table 1 continued
Study Data
Results Comments
Johnston and Rud- 1982 Census of service in-
The average annual earnings of non- Hospitals, educational institutions,
ney 1987 dustries
prot workers are 21.5 percent and religious organizations ex-
less than those employed in for- cluded. No controls for individual
prot rms. characteristics.
Leete 2001 1990 Census, 5 percent
No overall nonprot wage differen- Estimated hourly wages may be sub-
public use microdata tial after including detailed con-
ject to measurement error. Ex- sample
trols for industry and occupation. tremely detailed industry-occupa-
Among specied 3-digit industries tion interactions could absorb
with statistically signicant non- nonprot effects.
prot differentials, positive and negative effects are equally likely.
Mocan and Tekin 398 child care centers in
Nonprot childcare employees work- Extensive controls for human capital
forthcoming Calif., Colorado, Conn.,
ing full-time part-time receive a and center characteristics. Discrete
and N.C., data from 6 20 percent hourly wage pre-
factor methods used to control for Spring 1993
mium and 8 10 percent higher to- unobserved heterogeneity. Stan-
tal compensation. Considerable dard errors not reported.
variation by type of nonprot and worker.
R uhm
and B
orkoski
999 Preston 1988
Abt Associates, 1976–77 Nonprot weekly wage premium of
Center characteristics, labor quality, National Day Care Center
5 to 10 percent for childcare work- parental participation, and donations
Supply Study ers in federally regulated daycare
controlled for. Some differences centers; no difference for other cen-
across center types could persist. ters. Results consistent with the for-
mer being less competitive and able to pay rents to workers.
Preston 1989 1990 Survey of Job Char-
OLS results for SJC imply negative SJC sample is small n 300. Ex-
acteristics SJC; May nonprot differential of 20 percent
clusion restrictions are questionable 1979 Current Population
for managersprofessionals, no effect for selectivity-corrected estimates.
Survey CPS for clerical workers; larger negative
Nonprot status inferred not ob- effects for both groups in CPS. Se-
served in CPS data. lectivity-corrected results sensitive
to model specication. CPS wage change regressions indicate no differ-
ential for clerical workers, statisti- cally insignicant 10 percent pre-
mium for managers and professionals. For-prot workers
more often have pensions, health in- surance.
Roomkin and Weis- Hay Management Consul-
Nonprot hospitals offer higher base Job complexity and hospital charac-
brod 1999 tants, 1992 hospital com-
salaries but lower bonus payments teristics controlled for; individual
pensation survey to six top managerial positions. To-
characteristics are not. Low response tal compensation is higher in three
rate 19 percent. positions and lower in three.
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Table 1 continued
Study Data
Results Comments
Shackett and Tapani National longitudinal sur-
Compared to private nonregulated in- Nonprot status not observed; in-
1987 veys of young men and
dustries, the nonprot wage differ- stead it is assumed to include all
young women ential is 11, 0, 214, and 28 per-
persons in hospital and educa- cent for white females, black
tional services industries. females, white males, and black
males. Weisbrod 1983
Same as Goddeeris 1988 PIL lawyers earn 20 percent less an-
Small sample size 53 PIL lawyers; nually than if employed in private
PIL lawyers may not be represen- sector. These attorneys are aware
tative of other attorneys in non- of the negative earnings effects
prots. Work hours and fringe and expect them to be permanent.
benets not controlled for. Differences in preferences consis-
tent with type of employment.
tions are so extensive as many as 20,000 industry-occupation interactions in some models that there is likely to be little variation in the type of employer within many
of the narrowly dened industry-occupation cells.
13
Most similar to the present research is DuMond’s 1997 analysis of data from the 1994– 1995 Current Population Survey Outgoing Rotation Groups CPS-ORG.
His cross-sectional regressions indicate a nonprot wage penalty of between 6 and 11 percent. Conversely, xed-effect estimates, exploiting data on individuals switching
between for-prot and nonprot employment, imply small 0 to 4 percent and statis- tically insignicant earnings gaps. Several factors reduce our condence in these
ndings. First, it is not clear how movements into or out of public sector are treated. Second, few respondents switch types of employment over the two-year period, de-
creasing the precision of the estimates. Third, endogenous mobility between sectors is not considered. Fourth, DuMond controls only for broad one-digit industries or
occupations, which might inadequately account for differences in the job characteris- tics of nonprot and for-prot employment. Each of these issues receives attention
below.
IV. Data