Longman Dictionary of Contemporary English
unrepresentative
adjective
EXAMPLES FROM OTHER ENTRIES
▪ These workers are unrepresentative of the general population.
EXAMPLES FROM CORPUS
▪ However, there is no reason to believe that the sample is unrepresentative in any way.
▪ Naturally this judgement has to be tempered by the unrepresentative nature of the sample of reports that it draws upon.
▪ One only has to look at the statistics to see how unrepresentative Xuxa's world is.
▪ Second, the telephone lists actually used for the sample were unrepresentative of the electorate.
▪ The problem is that they are a small sample of all criminals, and almost certainly unrepresentative.
▪ The result is only representative on those variables selected for the quota, and may be quite unrepresentative on other factors.
Wiktionary
unrepresentative
a. Not representative
WordNet
unrepresentative
adj. not exemplifying a class; "I soon tumbled to the fact that my weekends were atypical"; "behavior quite unrepresentative (or atypical) of the profession"