Are particular school subjects associated with better performance at university?

2. School achievement and university performance

Achievement at school ⁵and subsequent university academic performance are highly correlated. Figure 1 (taken from Engler 2010, figure 4, page 20) shows the relationship. The students whose results are shown in the figure all achieved the NCEA level 3 qualification, and met the university entrance requirement.

Figure 1: Expected probability (and 90 per cent confidence limits) of passing most (more than 75 per cent) first-year bachelors courses at university by school achievement

Results are calculated using all ethnic groups, all study types, all degrees studied at university, all school decile categories, gap and no gap year students, and both genders. They exclude extramural students. The achievement score is explained in footnote 5.

The mean school achievement score for this population of students is about 50. It can be seen that for students with below-average school achievement, the relationship between school achievement and university performance is quite strong, and essentially linear. For every 5 point improvement in school achievement, there is a corresponding increase of about 10 percentage points in the likelihood of passing most first-year courses. For above-average school students, the relationship is less strong: improving school achievement results in small and decreasing improvements in university performance. This is to be expected, as the likelihood of passing most first-year courses nears certainty.

Footnote

5. Achievement at school is measured using a statistic named the NCEA level 3 achievement score. This score is based on students’ grades in their level 3 standards against other students in the same year, producing a score between 0 and 100. Students who gained level 3 credits with excellence and merit grades will score higher than students who gained their credits with relatively fewer merits or excellences, or with relatively more achieved grades. The score also adjusts for the level of difficulty within a standard. A student, who achieved an excellence in a standard where many people gained a merit or excellence, will receive a lower score for that standard, while a higher score is given to a similar student in a standard where most people received an achieved grade, for example. Details about the National Certificate of Education Achievement can be found at http://www.nzqa.govt.nz/qualifications-standards/qualifications/ncea/. Further details about the calculation of the school achievement score can be found in Ussher (2008).