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    Confidence bands for a linear regression with X and Y errors




    Dear all,

    I have been searching for a while without finding a solution, so I hope someone here can help.

    Here is my problem:

    I have (X, Y) data points. X is a roughness parameter for which I have several measurements, Y is the area of cells when they grow on a surface with the roughness X, for which I also have several measurements. Therefore for each pair (X;Y), X and Y are the mean values of a set of measurements, with standard deviations Sx for the X values and standard deviations Sy for the s values. One comment (I don't know if it matters): Sy does not correspond to an uncertainty in the measurement of a single cell, but to the variation of the area in a population of cells

    To show the correlation between X and Y, I would like to perform a linear regression taking into account the standard deviations. I think I found a way to do that, using the approach described in the attached PDF.

    First question: is that approach OK in my case ?
    Second question : I would like to compute 90% confidence bands. Is there a simple way to do that ? I found the answer only for the case of a simple linear regression (with no standard deviations associated to X and Y measurements)

    Thank your your help,

    Quentin
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    Re: Confidence bands for a linear regression with X and Y errors

    The type of regression to which you refer is called Deming Regression. See: https://en.wikipedia.org/wiki/Deming_regression


    This should answer your question. http://ncss.wpengine.netdna-cdn.com/...Regression.pdf

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    Re: Confidence bands for a linear regression with X and Y errors

    Thank you very much for your quick reply. The link for the PDF appears to be dead, could you attach it here ? Thanks again !

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    Re: Confidence bands for a linear regression with X and Y errors

    It worked great the first time, but I am getting the same error now. Here is a link to the cached version. http://webcache.googleusercontent.co...&ct=clnk&gl=us

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    Re: Confidence bands for a linear regression with X and Y errors

    Another resource: http://influentialpoints.com/Trainin...ssumptions.htm


    Note: Deming Regression also goes by Orthogonal Regression and Errors-in-Variables regression.

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    Re: Confidence bands for a linear regression with X and Y errors


    Thank you very much, that helps a lot !

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