Results 1 to 5 of 5

Math Help - Urgent Help Needed- Interpretation of Categorical Variables

  1. #1
    Newbie
    Joined
    Oct 2012
    From
    UK
    Posts
    7

    Exclamation Urgent Help Needed- Interpretation of Categorical Variables

    Thank you for taking the time to read this!!

    I am really stuck with a regression I am doing for my dissertation. Basically it is the categorical variable that is confusing me. The categorical variable 'industry' has three levels - yes, no, or next (indicating whether there is or isnt industry, or whether there is industry in the next state) I also have two other independent variables. My dependent variable is Forest Loss.

    When I run the regression in R industrynext 'disappears' (is this something to do with it being a reference var? I really dont know). industryno is significant and industryyes is not.

    How would I interpret industryyes and industryno, and what/ where is industrynext??

    I hope this has made sense!!

    Thank you for any help.
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor
    Joined
    Sep 2012
    From
    Australia
    Posts
    3,607
    Thanks
    591

    Re: Urgent Help Needed- Interpretation of Categorical Variables

    Hey larrikinlover.

    What is your specific model that you supplied to R?
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Newbie
    Joined
    Oct 2012
    From
    UK
    Posts
    7

    Re: Urgent Help Needed- Interpretation of Categorical Variables

    Hello my model is -

    lm(ForestCoverKm2~Industry+CitySize+DistanceBelem+ FedRoad)

    And the output is -
    Residuals:
    Min 1Q Median 3Q Max
    -20416 -6273 -249 2585 124963

    Coefficients:
    Estimate Std. Error t value Pr(>|t|)
    (Intercept) -8.308e+03 2.630e+03 -3.159 0.00195 **
    Industryno 4.733e+03 3.471e+03 1.364 0.17489
    Industryyes 5.391e+03 2.794e+03 1.930 0.05571 .
    CitySize 2.027e-03 1.130e-02 0.179 0.85793
    DistanceBelem 2.357e+01 4.539e+00 5.194 7.29e-07 ***
    FedRoad 5.535e+03 2.607e+03 2.124 0.03550 *
    ---
    Signif. codes: 0 *** 0.001 ** 0.01 * 0.05 . 0.1 1

    Residual standard error: 14410 on 137 degrees of freedom
    Multiple R-squared: 0.2518, Adjusted R-squared: 0.2245
    F-statistic: 9.222 on 5 and 137 DF, p-value: 1.382e-07
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Newbie
    Joined
    Oct 2012
    From
    UK
    Posts
    7

    Re: Urgent Help Needed- Interpretation of Categorical Variables

    Is there anyone that can help with this?

    The deadline for the paper is tomorrow- I would really appreciate any advice.
    Follow Math Help Forum on Facebook and Google+

  5. #5
    MHF Contributor
    Joined
    Sep 2012
    From
    Australia
    Posts
    3,607
    Thanks
    591

    Re: Urgent Help Needed- Interpretation of Categorical Variables

    You need to setup of dummy variables for categorical regression.

    Set up two dummy variables where you have:

    A B
    0 0 - First level
    1 0 - Second level
    1 1 - Third Level

    where A and B are dummy variables with each level being a realization of a particular category.

    Then each estimated parameter corresponds to the average number of realizations for that category.

    Have you taken a course or read up on Generalized Linear Models/Linear Models before?
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Repeated-measures categorical variables
    Posted in the Advanced Statistics Forum
    Replies: 0
    Last Post: April 3rd 2012, 07:20 AM
  2. Replies: 0
    Last Post: August 22nd 2011, 05:12 AM
  3. urgent help needed!
    Posted in the Advanced Applied Math Forum
    Replies: 3
    Last Post: December 17th 2009, 11:59 PM
  4. Replies: 0
    Last Post: November 4th 2008, 08:21 PM
  5. Urgent Help Needed! Any Help Will Do
    Posted in the Business Math Forum
    Replies: 1
    Last Post: October 10th 2008, 05:21 AM

Search Tags


/mathhelpforum @mathhelpforum