I have a question regarding the coefficient of determination. Wikipedia says:

*An interior value such as R^2 = 0.7 may be interpreted as follows: "Seventy percent of the variation in the response variable can be explained by the explanatory variables. The remaining thirty percent can be attributed to unknown, lurking variables or inherent variability."*

Shouldn't this be "Seventy percent of the

**squared**variation in the response variable can be explained by the explanatory variables"?

I know I'm probably wrong since I've seen the same interpretation on several sites

Thanks