Statistics work

 The results of voter surveys and polls guided the political campaigns of
many presidents and their opponents and advised news groups on which
political strategies are working. While polls have an important role in the
political process, they are anything but perfect tools for measuring and
forecasting voter behavior. Public opinion often changes daily or weekly (or
so the polls report this to be the case). And even worse, competing polls
report contradictory results over the same period of time. How are you to
know which polls to trust, if any?
Look at http://www.ncpp.org/?q=node/4 (20 Questions a Journalist Should Ask
About Poll Results) and http://www.pollingreport.com (Polling Report).
Answer the following two questions.

DISCUSSION QUESTION 1 - SIZE VS. VALIDITY: In evaluating a poll, a larger
sample size would be considered more favorably, but what consideration would
you consider even important than the sample size before trusting the
validity of a poll?