Can someone explain to me what exactly is the formula for Correlation coefficient R^2 Rsquare.
The formula mentioned in the Analyst Drive guide is. R^2 = 1 - [(Vi - Ci)^2 / (Cavg - Ci)^2]
But the values of Initial and Final R squared mentioned in the Volume Report doesn't use this formula.
I used another built-in function in excel to calculate R-squared values but still it's not exactly the same values.
R^2 = 1 - ∑(i=1 to N) [(Vi - Ci)^2 / (Cavg - Ci)^2]
here for Initial R^2. I am using
Vi= Initial volumes at i screenline
Ci= Observed volumes at i screenline.
Cavg= Average value of Observed volume whole set
Similarly for Final R^2
Vi= Estimated volumes at i screenline
Am I using this formula correctly?