Statistics in Education and Psychology

8

Standard Score and T-Score

There are various methods used in the scaling of psychological and educational mental test data. Many of them are based upon the normal probability curve. As used in mental measurement, a scale is a continuum or continuity along which item tasks, problems, etc. have been located in terms of difficulty or some other attribute. In standard score conversion, the raw scores are first converted into (σ) scores which are further converted into a new distribution with m and (σ) so selected as to make all scores positive and relatively easy to handle.

In this chapter, we shall consider some ways of transforming raw score scales into other scales for various reasons. One objective is to effect a more reasonable scale of measurement. ...