When we consider data quality, what are the differences among validity, reliability, and representativeness? How can you know the data have high levels of these characteristics?

Validity is the degree to which the research measures what it has to measure. High validity = Proper Research Design.

Reliability is the measure to which research measurement techniques are free of error or mistakes. High realiability = Reasearchers know the sample fully understands the question asked.

Representativeness is the extent to which consumers in a study are similar to the larger group of interest. High representativeness = Sample is large and chosen in an unbiased way.