Re: [R] confidence interval or error of x intercept of a linear regression

I should probably also add the health warning that the delta-method approach to ratios of coefficients is REALLY BAD unless the denominator is well away from zero. When the denominator is near zero nothing really works (Fieller's method is valid but only because 'valid' means less than you mi

Re: [R] confidence interval or error of x intercept of a linear regression

On Mon, 23 Mar 2009, Kevin J Emerson wrote: > Now, it is simple enough to calculate the x-intercept itself ( - intercept / > slope ), but it is a whole separate process to generate the confidence > interval of it. I can't figure out how to propagate the error of the slope > and intercept into

[R] confidence interval or error of x intercept of a linear regression

Hello all, This is something that I am sure has a really suave solution in R, but I can't quite figure out the best (or even a basic) way to do it. I have a simple linear regression that is fit with lm for which I would like to estimate the x intercept with some measure of error around it (conf