166 P. Christie, M. Shannon Economics of Education Review 20 2001 165–180
are made. Section 4 presents econometric estimates of male and female earnings equations and assesses the
importance of disaggregated education data in explaining variation in earnings. The log-earnings gap is decom-
posed into residual and explained parts and the share of education in explaining the gap is calculated in Section
5. Section 6 compares the results to those of earlier stud- ies.
2. Data
The data used in this paper are from the public use subsamples of the 1986 and 1991 Canadian censuses.
2
The earnings data apply to the years 1985 and 1990. The focus is on the sample of wage and salary earners who
worked full-time and full-year
3
and who were aged 25– 64. From our perspective, the availability of detailed
educational attainment information is the principal advantage of using the Census to study the gender wage
gap while information on field of study dictates the choice of census years 1986 and 1991. Other important
advantages of census data include the large sample size, and consequent increased statistical reliability of the
results, and the detailed data on personal characteristics it contains. The main disadvantage of using the Census
to study earnings differentials is its lack of information on job characteristics other than industry and occupation.
A brief overview of the Canadian education system which the education variables describe is provided in the
Appendix A. The public use version of the Census microdata file contains seven education variables in 1986
and ten in 1991. All but one of the variables measures the level of educational attainment. The most complete
of these is “Highest Level of Schooling” which con- tained 11 categories in 1986 and 14 in 1991.
4
The remaining educational variable in each data set reports
the field of study for those with post-secondary qualifi- cations.
This array of education variables is generous in com- parison to those available in other Canadian microdata
surveys. For example, the public use version of the much used Labour Market Activity Survey 1986–87, 1988–
90 contains one educational attainment variable with seven possible values. Educational detail in the Survey
of Consumer Finances, Canada’s main source of annual
2
The subsample is a 2 1986 or 3 1991 sample of Canadian households.
3
The definition of full-timefull-year used is: worked at least 30 hoursweek for 49 to 52 weeks of the year. Focus on this
subsample ignores any effect education may have on earnings through its effects on hours and weeks of work.
4
The other attainment variables provide details on years of schooling by level or information on degree attained.
income data, is similarly limited. Furthermore, earlier versions of the census lack data on field of study.
5
The main education variable used in the analysis below combines the “Highest Level of Schooling” and
the “Highest Degree, Certificate, Diploma Attained” variables. The resulting composite variable has nineteen
classifications which are reported in Table 1 along with the shares of the samples of full-time, full-year workers
who fall into each of these categories in the 1991 and 1986 censuses.
In the 1991 census, the largest shares of men and women are found in the four categories: grades 9–13,
high school graduate, non-university certificate and Bachelor’s degree. Together these levels accounted for
about 54 of the male sample and 62 of the female sample. Men are more likely than women to have less
than high school education 23 vs. 20 in 1991 while women are more likely to be high school graduates by
nearly the same margin. The male share was nearly twice the female share across the three trades categories in
1991. Women were more likely to have a non-trade, non- university certificate or diploma than men. There were
near equal shares of men and women with Bachelors degrees while the male shares were higher for graduate
level degrees.
The pattern of educational attainment was similar in the 1986 Census. The most notable changes between
1986 and 1991 were the decline in the share of those with the lowest levels of education, the rise in the share
with high school and the rise in the shares with univer- sity degrees.
The changes in educational attainment over time become more evident in Table 2 which reports 1991 edu-
cational attainment by age group. The shares with the lowest levels of education are much larger for the older
age groups. There are correspondingly larger shares of university educated workers and workers with post-sec-
ondary certificates among the younger groups. It is also apparent that educational attainment of women has been
improving relative to men. The share of younger women with university degrees is much higher than for older
women and has actually overtaken the share of young men with degrees. Women’s educational attainment has
also improved relative to men at the lower end. The share of women with less than high school has fallen more
sharply across age groups for women — for 55–64 year- olds this share was roughly 40 for both sexes but had
fallen to 18.5 for men and 13.5 for women in the 25–34 age group.
The figures in Tables 1 and 2 are for a sample of full-
5
The 1984 National Graduates Survey and the 1982 Gradu- ates Survey used by Wannell 1990 contain more detailed field
of study data than the census. The sample is however limited to post-secondary graduates from a single year.
167 P.
Christie, M.
Shannon Economics
of Education
Review 20
2001 165–180
Table 1 Educational attainment of full-time workers, full-year workers
Acronym Definition
1986 census 1991 census
Women Men
Women Men
Share number
Share number
Share number
Share number
LT5 Less than grade 5
1.2 411
1.2 734
0.8 527
0.9 927
GR58 Grade 5–8
6.0 2101
8.4 5076
3.9 2729
5.4 5814
GR913 Grade 9–13
19.8 6907
19.6 11850
15.6 10919
16.7 18087
HS High school graduate: no further education
16.6 5780
11.8 7107
18.6 12989
13.5 14638
TRD1 Trades certificate or diploma: no post-secondary
2.4 838
4.8 2918
3.4 2362
6.3 6846
SPNHS Some non-university post-secondary, no
5.0 1744
4.1 2472
5.0 3489
3.7 3999
certificatediploma, not a high school graduate SPHS
Some non-university post-secondary, no 5.8
2025 9.5
5726 5.6
3899 10.4
11255 certificatediploma, is a high school graduate
TRD2 Non-university post-secondary, trades certificate
14.4 5000
9.6 5775
16.2 11329
11.3 12216
PSCD Non-university post-secondary, with
14.4 5000
9.6 5775
16.2 11329
11.3 12216
certificatediploma SUNHS
Some university, no degree, not a high school 0.8
268 0.8
494 0.1
74 0.1
117 graduate
SUHS Some University, no degree, high school graduate
2.8 967
3.4 2022
3.6 2542
3.9 4228
UTRD3 University, with trades certificate
0.7 256
1.1 690
0.7 479
1.2 1310
UNUC University, with non-university certificatediploma
3.5 1216
2.7 1624
3.8 2625
2.8 3073
ULTB University graduate: other diploma or certificate
3.5 1213
2.3 1376
3.5 2482
2.2 2397
below Bachelor’s BACH
University graduate: Bachelor’s degree 10.6
3684 11.3
6787 11.9
8332 12.3
13375 BACH
+ University graduate: above Bachelor’s
1.8 624
1.8 1058
2.2 1512
2.0 2199
UPROF University graduate: professional degree
0.2 59
0.3 194
0.2 135
0.4 463
MASTER University graduate: Master’s degree
2.1 732
3.7 2231
2.6 1815
3.9 4221
DOCT University graduate: Doctorate
0.3 119
1.2 699
0.3 186
1.0 1123
Total sample 34 831
60 306 69 945
108 323 Duncan segregation index
12.8 14.0
168 P. Christie, M. Shannon Economics of Education Review 20 2001 165–180
Table 2 Educational attainment by age and sex per cent, 1991 census
Age group 25–34
35–44 45–54
55–65
Women Less than grade 5
0.2 0.5
1.2 2.8
Grade 5–8 0.9
2.7 7.3
12.9 Grade 9–13
12.4 14.6
19.0 24.4
High school graduate: no further education 17.5
20.6 18.0
15.5 Trades certificate or diploma, no post-secondary
3.2 3.4
3.6 3.7
Some non-university post-secondary, no certificatediploma, not a high school graduate 1.9
1.9 2.6
3.6 Some non-univeristy post-secondary, no certificatediploma, is a high school graduate
6.3 4.8
3.9 3.5
Non-university post-secondary, trades certificate 6.3
5.2 5.3
5.1 Non-university post-secondary, with certificatediploma
19.2 15.3
14.4 11.8
Some university, no degree, not a high school graduate 0.1
0.1 0.1
0.2 Some university, no degree, high school graduate
4.4 4.0
2.5 1.7
University, with trades certificate 0.8
0.7 0.6
0.4 University, with non-university certificatediploma
4.6 4.0
2.9 1.7
University graduate: other diploma or certificate 2.4
3.7 4.9
4.3 University graduate: other diploma or certificate below Bachelor’s
2.4 3.7
4.9 4.3
University graduate: Bachelor’s degree 15.5
12.1 8.4
5.1 University graduate: above Bachelor’s
2.0 2.6
2.1 1.2
University graduate: professional degree 0.3
0.2 0.1
0.1 University graduate: Master’s degree
2.0 3.2
2.8 2.0
University graduate: Doctorate 0.1
0.3 0.4
0.1 Sample size: Women
24 330 24 805
15 057 5753
Men Less than grade 5
0.4 0.5
1.2 3.0
Grade 5–8 1.5
3.1 9.1
16.6 Grade 9–13
16.6 14.9
17.4 21.2
High school graduate: no further education 14.9
13.8 12.4
10.6 Trades certificate or diploma, no post-secondary
5.1 5.9
7.7 8.4
Some non-university post-secondary, no certificatediploma, not a high school graduate 1.9
1.8 1.8
2.0 Some non-university post-secondary, no certificatediploma, is a high school graduate
5.2 3.8
2.3 1.6
Non-university post-secondary, trades certificate 11.1
10.6 9.5
9.3 Non-university post-secondary, with certificate diploma
13.9 11.6
9.1 6.5
Some university, no degree, not a high school graduate 0.1
0.1 0.1
0.1 Some University, no degree, high school graduate
4.2 4.5
3.3 2.6
University, with trades certificate 1.2
1.4 1.1
0.8 University, with non-university certificatediploma
3.5 3.0
2.3 1.4
University graduate: other diploma or certificate below Bachelor’s 1.6
2.4 2.8
2.3 University graduate: Bachelor’s degree
14.1 14.0
10.0 6.4
University graduate: above Bachelor’s 1.4
2.4 2.5
1.9 University graduate: professional degree
0.4 0.4
0.4 0.6
University graduate: Master’s degree 2.4
4.8 5.2
3.1 University graduate: Doctorate
0.3 1.0
1.9 1.9
Sample size: Men 36 079
36 526 24 23
11 487 Duncan Segregation Index
13.0 14.0
17.7 19.3
time, full-year workers — a select group, especially for women. Educational attainment is lower for the general
population.
6
This partly reflects the larger numbers of older workers and partly the increased likelihood that
better educated workers will work.
6
The share of the general population age 25–64 with less than high school is 26 compared to 22 for the sample of
full-time, full-year workers. The share with a Bachelors degree
Table 3 reports field of study of those with post-sec- ondary qualifications, a group which accounts for
roughly half the sample. For women, the most common fields were secretarial science, business, education and
nursing. These accounted for over 62 of qualifications
is 10.6 against 12.1 for the subsample. Differences from the subsample are greater for women especially at low educational
attainment but relative educational attainments are qualitatively
169 P. Christie, M. Shannon Economics of Education Review 20 2001 165–180
Table 3 Field of study of post-secondary graduates
Acronym Field name
1986 census 1991 census
Women Men
Women Men
Share number
Share number
Share number
Share number
Share of post-secondary graduates: EDREC
Educationrecreation 15.1
2838 6.0
1733 15.9
5591 6.1
3564 ARTS
Fine and applied arts 4.6
729 2.7
780 5.5
1948 2.7
1586 HUMAN
Humanities 8.1
1270 5.9
1709 6.8
2377 4.8
2832 SOCSC
Social sciences 8.9
1411 8.9
2580 9.2
3227 8.7
5066 BUS
Business 13.6
2149 16.9
4913 15.6
5491 16.7
9756 SECR
Secretarial 19.0
3003 1.2
356 16.7
5867 0.09
523 AGRBIO
Agriculturebiology 3.8
606 4.3
1252 3.7
1286 4.3
2509 ENGIN
Engineeringapplied science 0.5
85 7.7
2230 0.7
259 7.6
4455 ENGTR
Engineeringapplied science 3.4
529 38.6
11 216 3.7
1312 39.9
23 350 technology and trades
NURS Nursing
15.0 2361
0.7 197
14.2 4979
0.6 364
HEALTH Health not nursing
5.3 839
2.1 615
5.5 1925
2.5 146
MATHPH Mathphysics
0.2 36
0.2 63
0.2 70
0.2 121
Share with post-secondary qualification
45.3 15 766
48.2 29 078
50.3 35156
54.0 58 478
Duncan segregation index
48.7 47.4
in both the 1986 and 1991 Censuses. Engineering and applied science dominates for men accounting for nearly
40 of qualifications in both years.
7
Business was a dis- tant second in terms of importance 16–17. The most
sizeable change in field of study between 1986 and 1991 was the fall in the share of women in secretarial science.
A breakdown of field of study by age shows that field of study patterns have not been nearly as stable as a com-
parison of 1986 and 1991 figures in Table 3 might sug- gest. Nursing and educationrecreation account for 38
of qualifications of women aged 55–64 in 1991 but only 21 of 25–34 year old women see Table 4. Business
qualifications, social sciences, health non-nursing and engineering have become more common for young
women. Engineeringapplied science dominates for both older and younger men but has diminished slightly in
importance. The biggest share increase for men between age groups has been the rise in those with social
science qualifications.
8
similar to those in Table 1.
7
This dominance reflects the concentration of non-univer- sity technical and trades qualifications in this group. Among
male post-secondary graduates with non-university qualifi- cations, 62.5 have engineeringapplied science as a field.
8
The patterns for those with university degrees are substan- tially different. For women, the most common fields were edu-
cation, social sciences, humanities and business. Together these accounted for about 34 of degrees in 1991. Business was most
common for men followed by engineering, social sciences, edu- cation and mathphysics — together accounting for 80 of
The value of the Duncan segregation index is reported in the last row of Tables 1–4. The index shows the share
of workers of one sex who would have to change attain- ment or field to equalize attainment or field shares
across genders and so provides a simple summary meas- ure of gender differences in educational outcomes.
9
The index equalled 14.0 for educational attainment in 1991
19.3 for the oldest group and 13.0 for those aged 25– 34 and 12.8 in 1986. Index values were much higher
for field of study 47.4 in 1991 and 48.7 in 1986. As
degrees. A breakdown of field of study by age at the university level reveals that business has been the fastest growing field
for both genders. 17.5 of women and 25.4 of men aged 25– 34 had business degrees in 1991 compared to 4.5 and 14.6
respectively for those aged 55–64. A larger share of younger than older women have degrees in social sciences while the
shares in education, the humanities and nursing have fallen. Younger men are more likely to have degrees in engineering,
the humanities and education and more likely to be in mathphysics or the social sciences. The trends in business
degrees, engineering and nursing have resulted in some conver- gence in field shares between the sexes.
9
The index is calculated as: 1
2
O
N i51
|M
i
2F
i
| where M
i
is the share of the male sample that is in category i, F
i
is the share of the female sample that is in category i and N is the number of categories for the variable of interest in this
case level of educational attainment or field of study.
170 P. Christie, M. Shannon Economics of Education Review 20 2001 165–180
Table 4 Field of study by age and sex, 1991 census
Age groups 25–34
35–44 45–54
55–64
Women Educationrecreation
11.3 17.1
22.6 17.2
Fine and applied arts 6.9
5.0 4.1
4.7 Humanities
6.2 7.4
6.7 7.0
Social sciences 11.1
9.1 6.7
5.4 Business
18.8 14.3
12.5 12.8
Secretarial 16.7
16.2 16.5
20.7 Agriculturalbiology
4.2 3.4
3.0 3.7
Engineeringapplied 1.1
0.7 0.3
0.3 science
Engineeringapplied 4.9
3.5 2.4
1.9 science
technologytrades Nursing
9.5 15.2
19.6 20.9
Health not nursing 6.4
5.5 4.0
3.7 Mathphysics
2.8 2.4
1.5 1.6
All other 0.2
0.3 0.2
0.3 Number with post-
13 689 12 598 6831 2038
secondary: Women Men
Educationrecreation 3.6
6.9 9.0
5.5 Fine and applied arts
2.5 2.6
2.8 3.5
Humanities 3.8
5.1 5.6
5.9 Social sciences
9.0 9.7
7.8 5.6
Business 17.6
16.7 15.7
15.3 Secretarial
0.6 0.8
1.1 1.9
Agriculturalbiology 4.5
4.3 4.0
4.3 Engineeringapplied
7.3 7.6
7.7 8.8
science Engineeringapplied
42.4 38.3
38.3 41.5
science technologytrades
Nursing 0.6
0.8 0.5
0.5 Health not nursing
2.5 2.3
2.6 3.4
Mathphysics 5.5
4.9 4.8
3.5 All other
0.2 0.2
0.2 0.4
Number with post- 19 909 21 018 12 689 4862
secondary: Men Duncan segregation
46.7 47.9
51.8 53.6
index
with educational attainment, the index for field of study was highest for older workers and lowest for those aged
25–34. Calculation of the segregation index for occu- pation and industry revealed substantial differences in
the type of jobs held by men and women. In 1986 the index was 30.5 for occupation and 44.0 for industry.
These figures had fallen to 29.1 and 41.9 respectively by 1991.
3. Role of education in determining wage differences
