VALID PERCENTAGES

Sometimes you want to compute percentages using only cases with real responses. For example, suppose you have asked 100 people whether life is exciting or routine, and 25 said that it is exciting, 25 said that it is routine, and 50 told you to bug off. It would be a bit misleading, though it is correct, to state that 25% of those people think that life is exciting. A naive reader or listener would probably assume that the other 75% of the people find life unexciting. That is not really true, since the remaining 75% include people who declined to answer as well as those who find life routine. You can describe the results better by saying that half of the people who answered the question find life exciting, and half find life routine. You should also mention that half of the people in your sample refused to answer the question. You can find the percentages based only on cases with real answers (so-called valid cases ) in the column labeled VALID PERCENT in the frequency table.