Answering "Why ln(length) is Better for ANOVA & F-Test Homework

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Homework Statement

I am using Anova to check if length is dependent of age. The question is, "why is it better to use ln(length)?"

How should I answer this?
I think both seems linear on the two plots(attachment)
But ln(length) gives lower F-value and isn't that a bad thing so why is it better to use? Both has p-value = 2.16*10^-16 in R.

F-value ln(length) = 483
F-value length = 522
 

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MaxManus said:
The question is, "why is it better to use ln(age)?"
You looked at ln(length) v age.

If that is the question, why didn't you look at answering the question?
 
D H said:
You looked at ln(length) v age.

If that is the question, why didn't you look at answering the question?

Sorry, the question is why is ln(length) vs age better than length vs age
 
Have tried to use a linear regression on the two models to see which is best by comparing R^2. On linear-linear I got 0.5678. To compute R^2 for log linear I first ran the regression ln(length) = b0 + b1*age
and then computed ^length^ = exp(^b0)exp(^b1^x) and estimated the R^2 between ^length^ and x. R^2 = 0.49, which is worse

where ^text^ means estimates for text
 
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