| Students must be sufficiently motivated in order to achieve the intended learning outcomes of their college courses. Research in education and psychology has found motivation to be context-dependent. Therefore, students' motivation is likely to differ from one semester to the next according to which courses students are taking. However, there are also instances in which motivation levels may not change over time. In order to determine whether motivation for coursework changes across the academic career (and, if so, what variables may be related to that change), it is imperative to use a measure of motivation that is theoretically and psychometrically sound. In addition, the measure should function consistently over time--that is, the motivation measure must demonstrate longitudinal invariance. The purpose of this research was to investigate the factor structure and longitudinal invariance of a measure of motivation for coursework--the Expectancy, Value, and Cost Scale (EVaCS)--for incoming and mid-career college students. Study 1 examined the factor structure of the EVaCS and found support for a correlated three-factor model. The longitudinal invariance of this model was examined in Study 2, and results established the EVaCS to be an invariant measure of motivation for coursework across the two time points. An analysis of latent mean differences showed no significant overall mean changes in Expectancy and Value over time, but a statistically and practically significant increase was found for Cost (p < .05, d = 0.46). In addition to establishing the EVaCS as a structurally sound instrument, this research has implications for the measurement of motivation for coursework and the theoretical conceptualization of motivation. |
