3: Data

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3.1 Introduction

As outlined in Chapter 2 the estimation of the input-output model and the making of projections of the number of students at various stages of the higher education system requires data on:

It is possible to estimate the model with data from just two consecutive years. In this report we use course enrolment in higher education and school enrolment data from 1993 and 1994, and course completions data in higher education from 1993. The population estimates are for 1993 and 1994 and projections for 1995 to 2001. The three data sets are described and their initial analysis reported in the following sections.

3.2 Course Enrolment and Completions Data

Data on course enrolment and completions is used to estimate the matrix of transition proportions. It was obtained from unpublished records kept by DEET. Course enrolment and completions data are stored on separate files as aggregated records. These aggregated files are derived from unit record files provided by each university funded by DEET. DEET releases only aggregated data to safeguard confidentiality of individual students.

Specially compiled course enrolment files for 1993 and 1994 and a course completions file for 1993 were obtained from DEET. These files are different from the files that DEET normally makes available in one significant respect. In the specially compiled files the course commencement date (month and year) of students is included instead of just the year since commencement (one, two, three or three plus).

A vast amount of information is stored on each file. However, not all the variables that are included in the enrolment files are included in the completions file. For example, variables indicating whether a student commenced the course as a school-leaver or not and that indicating the mode of attendance, that is full-time, part-time or external, are not included in the completions file. This means that the analysis that can be performed will be limited by what is contained in the completions file.

The course enrolment files contain information on thirty two variables, and the course completions file on only thirteen of these. At this stage the analysis is restricted to looking at the system at the national level, although the model is equally applicable at the state/territory level. Only the following seven variables are used to estimate the input-output model:

The 1993 enrolment file has over 355,000 records while the 1994 file has over 370,000 records. The 1993 completions file has just under 86,000 records. SAS software was used to read and interrogate the data files on an Alpha machine. A variable giving the year of enrolment in the system since course commencement, Y, was generated from the course commencement date. In order to be consistent with DEET's definition of a commencing student the following definition was used for this variable:

,

where Ref_year is the year of the data file, Year is the year in which the course was commenced and month is the month in which the course was commenced. It should be noted that DEET defines a commencing student as one who is in his/her first year of a particular course at a particular institution. This means that a student who for some reason changes course or begins another degree after having completed one, is classified as a commencing student for a second time even though he/she may not be new to the university or faculty.

Preliminary analysis of the data revealed that students' age ranged from zero to ninety-eight! There is no reasonable explanation than coding error for the existence of students of age zero or 98. There was also some doubt about students who were in their nineties, and therefore, anybody whose age was zero or over 89 years was excluded from the analysis. This process resulted in the removal of 240 students in the 1993 enrolment file, 54 in the 1994 enrolment file and 25 in the 1993 completions file.

A value of negative one for Y in the 1993 course completions file implies the commencement date of between April 1994 and December 1994 for these students. A coding error is the most likely explanation for such a value of Y. There were a number of students whose commencement and completion times were between April 1993 and December 1993 (Y equal to zero). Similarly Y equal to zero in the enrolment file for 1994 indicates that some students' commencement date is after March 1994.

In order to be consistent with the data in the enrolment file for 1993, students for whom the variable Y is less than one are excluded from further analysis. This resulted in the removal of 122 students (109 undergraduates and 13 postgraduates) from the 1994 enrolment file and 598 (300 undergraduates and 298 postgraduates) from the 1993 completions file. Since the number of such students is relatively small, their exclusion is unlikely to significantly affect the estimation of the models. Moreover, by not excluding them the model building exercise can become unnecessarily complex.

Undergraduates

According to DEET (1995a) there are two categories of undergraduates-Bachelor and Other Undergraduates. Six courses of varying length are included under these two categories. We have defined undergraduates as those students enrolled for the following three courses:

These three courses generally take three to four years of full-time study and tend to form a homogeneous group among the undergraduate courses. They comprised over 95 percent of all undergraduate enrolment in 1993 and 1994. A number of diploma courses have been converted to Bachelor courses in recent years, most notably in the nursing and teaching area.

The data on undergraduates is examined by four characteristics:

The number of years of enrolment has six categories-one, two, three, four, five and six or more.

Eleven broad fields of study are considered. These are:

These fields are the same as those defined by DEET (1995a) with two exceptions. First, Education has been split into two fields of study-initial training and the other. The initial training part of education is of importance in its own right because a high proportion of the supply of new graduate teachers come from this category. This field will be referred to as Education (I) and the rest of education as Education (O). Secondly, Medicine (not medical science) and Dentistry (not dental therapy) has been taken out of Health and combined with Veterinary Science to form one field which from now on will be referred to as Medicine. Combining Medicine, Dentistry and Veterinary Science into one field makes statistical sense because all three courses generally take about five years to complete.

As an initial analysis, tables were constructed to show:

This was done for each broad field of study. Moreover, the gender balance in each group defined by age and field of study, and number of years of enrolment and field of study, was investigated. In general, there was no significant difference between 1993 and 1994 in the age profiles, and the distribution by number of years of enrolment. Thus, only the analysis for students enrolled in 1994 is reported.

The age profile of students enrolled in undergraduate courses in 1994 is given in Table 3.1. The Australian category does not include students who are full fee-paying and from overseas. Only Australian students are included in the data for each broad field of study. Overall 34 percent of male students are under 20 years of age compared to 37 percent of female students. Similar percentages in the 20-24 age group are 41 and 35, and in the over 24 age group 26 and 28, for male and female students, respectively.

Table 3.1 Age Distribution of Undergraduates who were Enrolled in a Course in 1994, by Sex and Field of Study

 
All
Australian
Agriculture
Architecture
Arts
Business
Education (I)
Age in Years Male Female Male Female Male Female Male Female Male Female Male Female Male Female
Under 187 8 7 9 6 9 6 8 6 8 7 9 5 9
1813 14 14 15 13 16 13 16 12 14 14 15 12 16
1914 15 14 15 16 17 14 17 13 14 14 16 15 18
2013 13 13 13 13 14 13 13 11 11 12 13 15 16
2111 9 11 9 11 10 11 11 9 7 10 9 12 11
228 6 7 6 7 5 9 10 6 5 6 6 7 5
235 4 5 4 4 3 7 7 5 3 4 4 4 3
244 3 3 3 2 2 4 5 4 2 4 3 3 2
25-2911 9 10 9 10 7 11 7 12 9 12 10 9 6
30-347 6 7 7 7 6 5 4 8 7 8 6 6 5
Over 348 12 9 13 11 9 5 3 15 19 9 8 12 9
Total 100 100 100 100 100 100 100 100 100 100 100 100 100 100
Under 2034 37 36 38 34 43 34 40 31 36 35 41 32 43
20-2441 35 39 34 37 35 44 46 34 29 37 35 41 37
Over 2426 28 25 28 28 22 22 14 35 35 29 24 27 20
 
 
Education (O)
Engineering
Health
Law
Medicine
Science
 
Age in Years Male Female Male Female Male Female Male Female Male Female Male Female

Under 18

0
1
9
12
6
7
5
6
7
7
9
13

18

1
1
17
19
13
14
8
11
11
12
16
19
19
1
1
17
20
14
15
11
12
14
15
16
18
20
2
4
16
18
12
12
11
13
14
14
14
15
21
5
8
13
13
9
7
11
13
16
15
11
10
22
5
8
8
7
7
5
10
10
14
14
7
5
23
5
7
5
3
5
3
6
6
9
8
4
3
24
5
7
3
1
4
3
3
3
4
3
3
2
25-29
23
18
7
3
11
10
12
9
6
6
9
6
30-34
16
11
3
1
8
9
8
6
3
3
5
4
Over 34
37
35
2
1
10
15
14
11
1
1
6
5

Total

100

100

100

100

100

100

100

100

100

100

100

100

Under 20 23 4351 3436 2430 3234 4150
20-24 2234 4543 3730 4244 5755 3936
Over 24 7664 136 3034 3426 1010 2015

Table 3.2 Age Distribution of Undergraduates who Completed a Course in 1993, by Sex and Field of Study

 
All
Australian
Agriculture
Architecture
Arts
Business
Education (I)
Age in Years Male Female Male Female Male Female Male Female Male Female Male Female Male Female
Under 18

0

0

0

0

0

0

0

0

0

0

0

0

0

0

18

0

1

0

1

0

1

0

0

1

1

1

1

0

1

19
7
12
7
12
4
6
8
10
8
13
10
14
6
16
20
17
21
18
22
17
21
17
20
18
23
21
26
18
27
21
19
17
19
17
21
29
18
21
16
16
20
21
18
18
22
13
10
13
9
14
15
13
13
10
8
11
10
11
8
23
9
6
8
6
8
4
11
9
7
5
7
6
5
5
24
6
4
5
4
6
4
8
9
4
3
5
4
4
3
25-29
13
10
12
9
11
10
15
10
12
8
12
8
11
6
30-34
7
6
7
6
8
5
6
3
9
6
7
4
9
5
Over 34
9
13
10
14
10
4
5
4
15
17
8
6
17
12
Total
100
100
100
100
100
100
100
100
100
100
100
100
100
100
Under 20
7
12
8
13
4
7
8
10
8
14
10
15
6
16
20-24
64
58
64
58
66
74
66
72
55
54
64
67
56
60
Over 24
29
30
28
30
29
19
25
18
36
32
26
18
37
24
 
 
Education (O)
Engineering
Health
Law
Medicine
Science
 
Age in Years
Male
Female
Male
Female
Male
Female
Male
Female
Male
Female
Male
Female
 
 
Under 18
0
0
0
0
0
0
0
0
0
0
0
0
 
 
18
0
0
0
0
0
0
0
0
0
0
1
1
 
 
19
0
0
2
4
7
12
2
4
1
2
11
15
 
 
20
4
6
18
25
18
21
6
9
1
2
23
28
 
 
21
4
7
27
33
14
13
17
18
11
13
22
22
 
 
22
5
7
19
18
9
7
21
22
31
32
12
11
 
 
23
5
7
11
7
6
5
15
12
25
25
7
6
 
 
24
4
6
6
4
4
3
6
7
13
11
5
4
 
 
25-29
20
18
11
6
16
12
12
11
12
10
10
8
 
 
30-34
17
11
4
1
9
10
7
7
3
3
5
3
 
 
Over 34
41
37
2
1
16
18
12
9
2
2
4
3
 
 
Total
100
100
100
100
100
100
100
100
100
100
100
100
 
 
Under 20
0
0
2
5
8
12
3
4
1
2
11
16
 
 
20-24
22
33
81
87
52
49
66
68
81
82
70
70
 
 
Over 24
78
66
17
8
41
39
32
27
17
15
19
14
 
 

The age profile of students vary a great deal by sex and also across fields of study. Except for the Education (O) field of study, in each field of study the proportion of females who are under 20 is higher than the proportion of males. For example, 43 percent of the females studying Education (I) are under 20 years old, but only 32 percent of the males studying Education (I) are in this age group. On the other hand in each field of study, except Medicine, the proportion of males who are 25 to 29 is higher than the proportion of females. In Medicine the proportion of males and females is the same in this age group.

Table 3.2 shows the age profile of students who completed courses in 1993. Most students tend to have finished the course when they were between 20 and 24 years of age. These data also have a pattern of variation which closely resembles that observed for the enrolment data.

The percentage breakdown by gender for students enrolled in 1994 is given in Table 3.3. For example, in Arts 25 percent of the under 18 age group is male and 75 percent is female. The aggregate figures indicate females outnumber males significantly in the younger age groups (20 years and younger) and the older age groups (30 years and over). However, this pattern is not uniform across all fields of study. Females seem to dominate across all age groups in Arts, Education (I) and Health, while male show dominance in Architecture and Engineering. In Science and Business males and females are in almost equal proportions in the younger age groups, but males are in higher proportions in the older age groups. Females are more numerous or equally as numerous as males in all age groups, except the over 24, in Law. In general, in Medicine there is a balance in the gender composition, except in the age groups between 21 and 29 when males are in higher numbers. Table 3.4 gives the gender balance in course completions. Once again, the pattern of variation is a reflection of that observed for the enrolment data..

Table 3.5 shows the variation in the number of years of enrolment (time in the system) for students by gender and field of study for 1994. For example, 31 percent of all female students in Architecture are in their first year of enrolment. On comparing with the data for 1993, which is not included in this report, 1994 data shows a significant increase in the percentage of both male and female students who are in the fourth or higher year of enrolment in Education (I), thus reflecting a reduced number commencing this field of study in 1994. Some differences between fields of study reflect the variation in the course length; for example, Engineering and Medicine are courses of longer duration, and thus, a higher proportion of students are in the fourth and fifth year of enrolment in these fields of study. Overall a female is less likely to be in her fourth or higher year of enrolment than a male is.

Table 3.3 Gender Distribution of Undergraduates who were Enrolled in a Course in 1994, by Age and Field of Study

 
All
Australian
Agriculture
Architecture
Arts
Business
Education (I)
Age in Years Male Female Male Female Male Female Male Female Male Female Male Female Male Female
Under 18
41
59
41
59
52
48
57
43
25
75
49
51
18
82
18
43
57
43
57
57
43
60
40
28
72
52
48
20
80
19
44
56
43
57
61
39
61
39
29
71
51
49
22
78
20
45
55
45
55
61
39
63
37
31
69
53
47
24
76
21
49
51
49
51
63
37
64
36
35
65
56
44
27
73
22
51
49
51
49
69
31
62
38
36
64
57
43
32
68
23
52
48
51
49
69
31
66
34
39
61
58
42
31
69
24
52
48
50
50
66
34
63
37
39
61
60
40
34
66
25-29
50
50
49
51
69
31
74
26
38
62
59
41
33
67
30-34
46
54
45
55
67
33
73
27
33
67
60
40
31
69
Over 34
36
64
35
65
68
32
73
27
26
74
58
42
30
70
Total
45
55
45
55
63
37
64
36
31
69
55
45
26
74
 
 
Education (O)
Engineering
Health
Law
Medicine
Science
 
Age in Years Male Female Male Female Male Female Male Female Male Female Male Female   
Under 18
11
89
83
17
16
84
43
57
52
48
49
51
 
 
18
16
84
85
15
17
83
41
59
50
50
52
48
 
 
19
18
82
84
16
17
83
47
53
50
50
54
46
 
 
20
12
88
84
16
19
81
46
54
52
48
55
45
 
 
21
15
85
86
14
21
79
47
53
54
46
58
42
 
 
22
15
85
89
11
24
76
51
49
53
47