An average is found when a group of factors are added together and then divided by the total number of factors. This way of finding averages is not necessarily applicable to averaging results of a survey. To present survey data using weighted averages may be the best way to convey the information.
What is a Weighted Average?
A weighted average is an average of factors when certain factors count more than others or are of varying degrees of importance. Weighted averages are often found in regards to assigning grades in school. Scores of exams may carry more weight that homework completion. Projects may count more than attendance or participation. All of these factors are combined to create a final grade for a student but each component of the final grade is not worth the same amount.
Weighted Averages and Surveys
When conducting a survey, you are asking a varied group of respondents the same question. If every respondent is counted individually and has the same importance, you could take a simple average to find the survey result. If you are surveying groups of various numbers of people, each group will not be counted equally or else the results will be skewed. In this case, you would assign various weights to the responses to keep the survey results as accurate as possible.
Why is a Weighted Average Important?
Let's suppose that you have broken a group of survey respondents into two smaller groups, groups A and B, and that group A has 10 more people in it than group B. If you were to average the answers together without weighting them, group B's answers would seemingly count more as there are fewer people to answer the question. In order to evenly distribute the answers, you must add weight to group A's answers. This will ensure your survey responses are more accurate.
How to Find a Weighted Average
In order to accurately distribute the responses of group A and B, you will need to find the weighted average. To do so, calculate the average response for group A and for group B. Multiply the number of respondents in group A by the average response of group A. Multiply the number of respondents in group B by the average response of group B. Add these two together and divide the total number of respondents from group A and B. This will weight the survey and allow you to analyze the data accurately.