Rasch analysis of examination results provides information about student performance and exam validity

Rasch Analysis is being used to examine chemistry exams across subjects and years. Rasch analysis uses a statistical and probabilistic method that converts the raw student performance on an exam - representing “ability” - and the performance of exam questions - representing “difficulty” - into a common scale of measurement called “logit”. Rasch Analysis allows the academic to compare the student versus question performance using a single measure of “performance”.

The Rasch method differs strongly from other statistical approaches since Rasch analysis is suitable to measure a single “construct” or constructs that are likely to be correlated. Unlike its counterparts, Rasch analysis is insensitive to class size once validated. This talk will briefly explain how Rasch analysis assesses data and the information that it provides. This will provide the background to the second talk which will present results of analysis of chemistry examination results.