Once you run a survey, you'll see the final results in the full survey report, as well as in the Surveys field when looking at your features. Wizeline's algorithm captures all survey responses and presents a percent score, like you see below.
If a feature was part of a single survey, the overall survey score is calculated by each user's ranking of that feature against other features in the survey.
If the feature was part of multiple surveys, the overall score shown in the full survey report relates to that feature's score within that survey. However, the score may appear different when looking at specific features in your backlog. This is because outside of the context of a specific survey, Wizeline's algorithm aggregates the results of all users who ranked the feature across all surveys in which it was involved.