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  1. #1
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    Log




    Dear all,

    Im am doing an OLS regression. My dependent variable has large negative values, many zeros and large positive values. How can I transform my data in such a way that I can take the log of this data?

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    Re: Log

    I don't get it, if you want to log it then go for it.

    Do yo have a more specific question?
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    Re: Log

    Log cannot be applied to negative values and zeros.

    To solve for zeros, I can add a constant (1) to each variable. But this does solve for the negative values.

    So my question is, how do I have to transform my data, so that I can take the log of the whole data set, including negative, positive and zero values.

    I hope I formulated my question more clear.

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    Re: Log

    What is your smallest value?
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    Re: Log


    If the negative values are real, i.e. not the result of some error, then taking logs makes no sense. One option is the cube root is a transformation; it is somewhat similar to a log but can handle negative values.

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