What are validity and reliability?
These are issues which are probably taken for granted in the kind of measurement you deal with in biological and physical sciences but they can be hard to achieve in the social sciences. When we are measuring attitudes and beliefs we are not dealing with tangible, observable identities like the number of plants germinated. There is nothing to calibrate our instruments against except our own theories and concepts. Despite the many, many problems with accurately and reliably measuring attitudes, the most common thing is for researchers to ignore the problems and treat the data as if it were implicitly accurate. This makes the whole exercise worthless. Reliability: This is whether a person would give consistent answers to your survey in different times, places or contexts. What we are getting at here is whether the answers you are getting are effected by things like the respondent s mood on the day, their health state or the weather. Validity: This is whether the questionnaire actually me
