[datatable-help] Fitting a line to a log-log graph

[hamilthj]

I am generating a simple body length-weight regression plot where the
variables form a logistic relationship on normal axes. To simplify the graph
and have the true variables on either axes, I've log transformed the axes
and the now linear relationship between the variables is obvious. 

I am having an impossible time trying to fit a line to this graph. 

    plot(Average.BL~Wet.weight, log="xy")
    reg=lm(log(Average.BL)~log(Wet.weight))
    reg   #used intercepts from output
    abline(log(2.9978), 0.3289, untf=F)

Here is the graph that's generated:

<http://r.789695.n4.nabble.com/file/n4725006/BL-Weight.png> 

Not sure where to go from here, the slope looks right but obviously the
intercept is offset and I'm not sure why.



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