APPENDIX: SOCIOECONOMIC FACTORS AND STUDENT ACHIEVEMENT - RESULTS OF LOGISTIC REGRESSION ANALYSIS
In order to gain a better understanding of the extent to which particular personal, family and household characteristics affect students' academic achievement, this appendix models the influence of a number of socioeconomic variables from the Census of Population and Housing on National Assessment Program – Literacy and Numeracy (NAPLAN) results. The analysis is based on a logistic regression analysis of socioeconomic factors influencing student achievement. The modelling results are broadly discussed throughout the Socioeconomic Factors and Student Achievement in Queensland article.
LOGISTIC REGRESSION ANALYSIS
Logistic regression is a popular and widely used statistical technique for modelling categorical outcomes, such as the probability of whether a student scores above or below the national minimum standard in reading.
The logistic regression model is generally expressed in terms of the odds of the event. For each characteristic a comparison group is selected. In the context of this paper, the "odds ratio" for each category represents the likelihood of students in that group scoring at or above the national minimum standard, in contrast to the comparison group. Values below one indicate a decreased likelihood of scoring at or above the NAPLAN national minimum standard, while values above one show an increased likelihood of scoring at or above the national minimum standard, relative to the comparison group.
It is important to note that the effect of socioeconomic factors on student achievement may be mediated by a range of other contextual, family and individual characteristics. Some of these other factors which are not explored in this regression analysis may include factors such as students' academic ability, parental support for learning, family cohesion, teacher quality and school facilities.
The extent to which particular characteristics affect the likelihood of attaining at or above national minimum standard NAPLAN results for reading, numeracy and writing domains across all grades is presented in Table 1. The information below mainly discusses the results for the variables which were statistically significant.
After controlling for the effects of the other variables included in the model, males were less likely to score at or above the NAPLAN national minimum standard for any of the three domains, than females. Similarly, students from a couple family with one parent employed were less likely than those for students with both parents employed to score at or above the national minimum standard for reading, but more likely than those where neither parent was employed.
The odds ratios for birthplace of parents show that students whose father or mother was born overseas were more likely to score at or above the national minimum standard for reading and writing than those with both parents born in Australia, while those with both parents born overseas were more likely than either of these groups to score at or above the national minimum standard for all three domains.
Parental education had a consistently positive influence on NAPLAN results. Relative to families where neither parent completed secondary school, the likelihood of students achieving at or above national minimum standard was higher for all three domains for students whose parents who had high education levels. The odds for students from couple families where both parents had completed higher education, or those with a lone parent who had completed higher education, were between 1.72 and 2.22 times the odds for students from couple families where neither parent had completed secondary school.
English proficiency also influences the probability of obtaining a score at or above the NAPLAN national minimum standard. Not surprisingly, students who were rated as speaking English 'not well' or 'not at all' did worse than those with better English skills, for reading, writing and numeracy. Interestingly, those who spoke a language other than English at home and spoke English 'very well' had a higher likelihood of obtaining a score at or above national minimum standard in reading and writing, than those who spoke English only.
After controlling for the effects of the other variables included in the model, the area that a student lived in (SEIFA quintile) had a consistent influence on student's NAPLAN results. Students who lived in the most disadvantaged areas (Quintile 1) were more likely to fall below the national minimum standard for numeracy, reading and writing, when compared with students who lived in the other four SEIFA quintiles.
Note that an odds ratio was not calculated for core activity need for assistance or for child type (e.g. foster or grandchild), due to populations in some categories of these variables being too small for modelling purposes.
TABLE 1. ODDS RATIO OF ACHIEVING AT OR ABOVE NAPLAN NATIONAL MINIMUM STANDARD, POOLED RESULTS ACROSS ALL GRADES
|Females (comparison group)||-||-||-|
|Aboriginal or Torres Strait Islander Status|
|Non-Indigenous (comparison group)||-||-||-|
|Aboriginal or Torres Strait Islander||0.62***||0.68***||0.69***|
|Major city (comparison group)||-||-||-|
|Parents Education |
| Both parents completed higher education||2.21***||2.22***||2.20***|
| One parent completed higher education||1.54***||1.54***||1.58***|
| Both completed secondary school||1.64***||1.62***||1.66***|
| One parent completed secondary school||1.28***||1.31***||1.31***|
| Neither parent completed secondary school (comparison group)||-||-||-|
|One parent family|
| Completed higher education||1.72***||1.92***||2.00***|
| Completed secondary school||1.63***||1.61***||1.92***|
| Did not complete secondary school||1.21||1.22||1.39**|
|Mother's birth age(a)|
|15 to 19 (comparison group)||-||-||-|
|20 to 24||0.96||1.03||1.04|
|25 to 29||1.05||1.09||1.13*|
|30 to 34||1.13||1.23***||1.30***|
|35 to 39||1.13||1.25***||1.35***|
|40 to 54||1.00||1.15||1.29**|
|Married(b) (comparison group)||-||-||-|
|Number of children in family|
|One (comparison group)||-||-||-|
|Four or more||0.89*||0.70***||1.00|
|Birthplace of parents|
|Both parents born in Australia (comparison group)||-||-||-|
|Both parents born overseas||1.24***||1.25***||1.36***|
|Father only born overseas||1.09||1.19***||1.15**|
|Mother only born overseas||1.11||1.17**||1.29***|
|Birthplace of student|
|Born in Australia (comparison group)||-||-||-|
|Arrival in Australia|
|Born in Australia or arrived more than 5 years ago (comparison group)||-||-||-|
|Arrived in the last 5 years||0.94||0.69***||0.85*|
|Speaks English only (comparison group)||-||-||-|
|Speaks English very well||0.97||0.88*||1.24***|
|Speaks English well||0.65***||0.52***||0.54***|
|Speaks English not well or not at all||0.41***||0.26***||0.25***|
|Weekly Household Income|
|Under $600 (comparison group)||-||-||-|
|$600 - $799||0.98||0.90*||0.90*|
|$800 - $999||0.97||0.91||0.79***|
|$1,000 - $1,249||0.93||0.91||0.81***|
|$1,250 - $1,499||1.02||0.95||0.85**|
|$1,500 - $1,999||0.93||0.90||0.84**|
|$2,000 - $2,499||0.87||0.86*||0.87*|
|$2,500 - $2,999||0.97||1.04||0.99|
|Quintile 1 - Most disadvantaged (comparison group)||-||-||-|
|Quintile 5 - Most advantaged||1.99***||1.84***||1.95***|
|Parents Labour Force Status |
|Couple family: Both employed||1.23***||1.11**||1.10**|
|Couple family: One parent employed (comparison group)||-||-||-|
|Couple family: Neither employed ||0.80***||0.79***||0.73***|
|One parent family: Employed||1.25||1.28||1.13|
|One parent family: Not employed||0.88||1.04||0.85|
|Type of internet connection|
|No internet (comparison group)||-||-||-|
|Owned outright (comparison group)||-||-||-|
|Mortgage: Costs <30%||0.90||0.96||0.89*|
|Mortgage: Costs 30%+||0.86*||0.85**||0.90|
|Rent: Costs <30%(c)||0.70***||0.76***||0.75***|
|Rent: Costs 30%+(c)||0.70***||0.74***||0.75***|
|*** Significantly different effect to the comparison group (p<0.001)|
|** Significantly different effect to the comparison group (p<0.01)|
|* Significantly different effect to the comparison group (p<0.05)|
|(a) Includes natural and adoptive mothers.|
|(b) Opposite sex couples only.|
|(c) Includes those renting from a private landlord only.|
|Note: An odds ratio of 1 indicates there is no difference from the comparison group.|
|Source: Integrated Queensland Education and ABS Census Dataset.|