How do I find the correlation coefficient of two variables with unequal number of data using Excel? And do I use the mean as data to calculate?
A correlation coefficient requires that for every x-value there be a y-value ... otherwise, how should I know how much value of y to attribute to x? For example, if you're trying to determine how much height correlates with age, you need a collection of heights and ages. Knowing that a person is 5'5" tall doesn't help at all if you don't know how old that person is.
Do you mean that you have several y values for each of your x values? Like
5-year olds: 36", 37" 38"
6-year olds: 37", 39", 40" ... ?
If so, make a row for each y value, and include its corresponding x-value:
Age | Height
5 | 36
5 | 37
5 | 38
6 | 37
6 | 39
6 | 40
And then you can use CORREL()