Validity and Reliability

Are we familiar with this? Validity and Reliability, lately we take up that matter then a long pause for the class was sink in.. let's know about it.

Validity 

Validity, in recent years, has been defined as referring to the appropriateness, correctness, meaningfulness and  usefulness of the specific conclusions that a teacher teaches regarding the teaching-learning situation. Content-validity refers to the content and format of the instrument.
       While content validity is important , there are other types of outward appearance of the test. It is the lowest form of test validity. A more important type of validity is called criterion-related validity. In criterion validity, the test item is judged against a specific criterion e.g. relevance to a topic like the topic on conservation, for example.

 Reliability

The reliability of an assessment method refers to its consistency. It is also a term that is synonymous with dependability or stability.
      Stability or internal consistency as reliability measures can be estimated in several ways. The Split-half method involves scoring two halves (usually, odd items versus even items) of a test separately for each person and then calculating a correlation coefficient for the two sets of scores.