I have to determine which method - mean, median, or mode - would be best for answering the following question:
Find the average number of athletes for the sample of 7 countries listed by deciding which measure of center is the best represntation of the number of athletes from each country. Also, if you omit Zimbabwe, how would that change the mean? Calculate new mean and decide how this affects the mean.
New Zealand - 15
Australia - 60
Canada - 221
Zimbabwe - 1
Brazil - 13
China - 66
USA - 230
Answers:
1. Best method: Would I use the median to find the average number of athletes since there are gaps in the middle? MEdian = 60
2. Mean without Zimbabwe
= 15+60+221+13+66+230/6
= 605/6
= 100.83
Mean with Zimbabwe
= 15+60+221+1+13+66+230/7
= 606/7
= 86.57
Without Zimbabwe, the average is much higher than if Zimbabwe is included.
The median gives you sort of a middle where half are above and half below.
Use the median because Zimbabwe, Canada, and the US are not representative. As you can see, Zimbabwe pulls the average way down but is really what is often called an "outlier".