Abstract
A test response that behaves abnormally is one that deviates from an expected pattern based on the student's actual ability. Time pressure can cause students' aberrant behaviour and obscure their true abilities, whether conditioned or unconditioned. This study examined the nexus between time pressure and mathematical ability in the spectrum of within-ability (W*) and beyond-ability (B*) responses. In this study, a factorial design of 2x2x2 was used. Five hundred and fifty grade 11 students from a high school in southwestern Nigeria were surveyed. The data was analysed based on ability measures (low vs high) and time pressure (conditioned vs unconditioned) as the independent variables, while aberrance responses measured as B* and W* were the dependent variables. Using MANOVA, inferential statistics were generated to determine the participants' ability and time pressure differences regarding their aberrance behaviour. According to the results, low-ability examinees showed more response aberration than high-ability examinees, as measured by W* and B*. Additionally, the analyses show that students with unconditioned time pressure respond more than those with conditioned time pressure, and the interaction between ability and time pressure was statistically significant (F (1,546) = 19.566, P = 0.001). Based on the findings, it is evident that time pressure inhibits mathematical ability and might lead to response aberrations. This study provides direction for future research on aberrance responses.