a term used, particularly in relation to the performance of schools, for a measurable impact on pupil attainment which is more than that statistically expected. In other words, it appears that the school has improved its learners' levels of attainment more than that of other schools. However, without very detailed knowledge of the nature of school composition - the socioeconomic background of learners - and their out-of-school experiences, it is by no means easy to attribute causes for such phenomena.
principled preferences; standards; judgement of what things are good, valuable, important (in life).
in statistics, the square of the standard deviation.
the process or fact of being established as authentic, accurate, or true.
a group of people who primarily interact by communication media rather than face-to-face.