To calculate the number of people who opted out of a group, which method should you use?

To determine how many people opted out of a group, identifying the number of unique individuals and accounting for any duplicates provides the most reliable calculation method. By recognizing duplicates, you ensure that each person is counted only once, giving you an accurate representation of how many individuals participated and, consequently, how many opted out.

This approach helps in distinguishing between those who may have expressed their decision to opt out multiple times and those who may have participated in the survey or study without opting out. Once you have established the number of unique individuals, you can then ascertain how many chose to remain in the group, from which you can derive the number that opted out.

Using total participants with duplicates can lead to an inflated number, while only considering those who explicitly said 'no' may overlook instances where individuals did not communicate their decision clearly. Estimating based on participation ratios could be too imprecise, as it doesn't take into account the actual responses from individuals concerning their participation status.

Therefore, the method of taking the number of unique people and subtracting duplicates accurately captures the essence of who is part of the group versus who has opted out, making it the most effective choice.