R, caret: does caret automatically create dummy variable for random Forest?












1












$begingroup$


I created a two class data set, dat. This data set only contains 25 variables. 24 are numeric and 1 is categorical (with 26 levels). The result of the auto-tuned model gives a mtry of 2, 14, 26, 38 and 50. So is this true that the caret created the dummy variable for the categorical variable? What other models does caret create dummy variable automatically?



Please see following example code.



pacman::p_load(R.utils, caret, doParallel)
cl <- makeCluster(8, outfile="")
registerDoParallel(cl)
set.seed(2)
dat <- twoClassSim(48842, noiseVars = 10)# 25 variables.

dat = cbind(dat,data.frame(categorical = sample(LETTERS,nrow(dat),replace = T)))

fit_on <- list(rs1 = 1:1300)
pred_on <- list(rs1 = 1330:10000)
indexFinal = 1:1000

fitControl <- trainControl(method = "cv",number=1,repeats=1,
classProbs = TRUE,summaryFunction = twoClassSummary,
index= fit_on, indexOut = pred_on,
indexFinal = indexFinal,
verboseIter = TRUE,
savePredictions = TRUE
)

model = train(Class ~ ., data = dat,
method = "rf",
preProcess=c("center","scale"),
trControl = fitControl,
tuneLength = 5)

model

# mtry ROC Sens Spec
# 2 0.9166711 0.9298806 0.6778085
# 14 0.9237881 0.8851236 0.7645137
# 26 0.9177710 0.8746803 0.7770797
# 38 0.9132661 0.8689258 0.7753204
# 50 0.9093577 0.8687127 0.7728072
# there are only 25 variables.

stopCluster(cl)









share|improve this question









$endgroup$

















    1












    $begingroup$


    I created a two class data set, dat. This data set only contains 25 variables. 24 are numeric and 1 is categorical (with 26 levels). The result of the auto-tuned model gives a mtry of 2, 14, 26, 38 and 50. So is this true that the caret created the dummy variable for the categorical variable? What other models does caret create dummy variable automatically?



    Please see following example code.



    pacman::p_load(R.utils, caret, doParallel)
    cl <- makeCluster(8, outfile="")
    registerDoParallel(cl)
    set.seed(2)
    dat <- twoClassSim(48842, noiseVars = 10)# 25 variables.

    dat = cbind(dat,data.frame(categorical = sample(LETTERS,nrow(dat),replace = T)))

    fit_on <- list(rs1 = 1:1300)
    pred_on <- list(rs1 = 1330:10000)
    indexFinal = 1:1000

    fitControl <- trainControl(method = "cv",number=1,repeats=1,
    classProbs = TRUE,summaryFunction = twoClassSummary,
    index= fit_on, indexOut = pred_on,
    indexFinal = indexFinal,
    verboseIter = TRUE,
    savePredictions = TRUE
    )

    model = train(Class ~ ., data = dat,
    method = "rf",
    preProcess=c("center","scale"),
    trControl = fitControl,
    tuneLength = 5)

    model

    # mtry ROC Sens Spec
    # 2 0.9166711 0.9298806 0.6778085
    # 14 0.9237881 0.8851236 0.7645137
    # 26 0.9177710 0.8746803 0.7770797
    # 38 0.9132661 0.8689258 0.7753204
    # 50 0.9093577 0.8687127 0.7728072
    # there are only 25 variables.

    stopCluster(cl)









    share|improve this question









    $endgroup$















      1












      1








      1





      $begingroup$


      I created a two class data set, dat. This data set only contains 25 variables. 24 are numeric and 1 is categorical (with 26 levels). The result of the auto-tuned model gives a mtry of 2, 14, 26, 38 and 50. So is this true that the caret created the dummy variable for the categorical variable? What other models does caret create dummy variable automatically?



      Please see following example code.



      pacman::p_load(R.utils, caret, doParallel)
      cl <- makeCluster(8, outfile="")
      registerDoParallel(cl)
      set.seed(2)
      dat <- twoClassSim(48842, noiseVars = 10)# 25 variables.

      dat = cbind(dat,data.frame(categorical = sample(LETTERS,nrow(dat),replace = T)))

      fit_on <- list(rs1 = 1:1300)
      pred_on <- list(rs1 = 1330:10000)
      indexFinal = 1:1000

      fitControl <- trainControl(method = "cv",number=1,repeats=1,
      classProbs = TRUE,summaryFunction = twoClassSummary,
      index= fit_on, indexOut = pred_on,
      indexFinal = indexFinal,
      verboseIter = TRUE,
      savePredictions = TRUE
      )

      model = train(Class ~ ., data = dat,
      method = "rf",
      preProcess=c("center","scale"),
      trControl = fitControl,
      tuneLength = 5)

      model

      # mtry ROC Sens Spec
      # 2 0.9166711 0.9298806 0.6778085
      # 14 0.9237881 0.8851236 0.7645137
      # 26 0.9177710 0.8746803 0.7770797
      # 38 0.9132661 0.8689258 0.7753204
      # 50 0.9093577 0.8687127 0.7728072
      # there are only 25 variables.

      stopCluster(cl)









      share|improve this question









      $endgroup$




      I created a two class data set, dat. This data set only contains 25 variables. 24 are numeric and 1 is categorical (with 26 levels). The result of the auto-tuned model gives a mtry of 2, 14, 26, 38 and 50. So is this true that the caret created the dummy variable for the categorical variable? What other models does caret create dummy variable automatically?



      Please see following example code.



      pacman::p_load(R.utils, caret, doParallel)
      cl <- makeCluster(8, outfile="")
      registerDoParallel(cl)
      set.seed(2)
      dat <- twoClassSim(48842, noiseVars = 10)# 25 variables.

      dat = cbind(dat,data.frame(categorical = sample(LETTERS,nrow(dat),replace = T)))

      fit_on <- list(rs1 = 1:1300)
      pred_on <- list(rs1 = 1330:10000)
      indexFinal = 1:1000

      fitControl <- trainControl(method = "cv",number=1,repeats=1,
      classProbs = TRUE,summaryFunction = twoClassSummary,
      index= fit_on, indexOut = pred_on,
      indexFinal = indexFinal,
      verboseIter = TRUE,
      savePredictions = TRUE
      )

      model = train(Class ~ ., data = dat,
      method = "rf",
      preProcess=c("center","scale"),
      trControl = fitControl,
      tuneLength = 5)

      model

      # mtry ROC Sens Spec
      # 2 0.9166711 0.9298806 0.6778085
      # 14 0.9237881 0.8851236 0.7645137
      # 26 0.9177710 0.8746803 0.7770797
      # 38 0.9132661 0.8689258 0.7753204
      # 50 0.9093577 0.8687127 0.7728072
      # there are only 25 variables.

      stopCluster(cl)






      machine-learning r






      share|improve this question













      share|improve this question











      share|improve this question




      share|improve this question










      asked Mar 17 '17 at 23:42









      WCMCWCMC

      23326




      23326






















          1 Answer
          1






          active

          oldest

          votes


















          0












          $begingroup$

          Yes, it does for some models. You can inspect which variables are used via
          model$coefnames.






          share|improve this answer








          New contributor




          Marcus Lauritsen is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
          Check out our Code of Conduct.






          $endgroup$













            Your Answer





            StackExchange.ifUsing("editor", function () {
            return StackExchange.using("mathjaxEditing", function () {
            StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix) {
            StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
            });
            });
            }, "mathjax-editing");

            StackExchange.ready(function() {
            var channelOptions = {
            tags: "".split(" "),
            id: "557"
            };
            initTagRenderer("".split(" "), "".split(" "), channelOptions);

            StackExchange.using("externalEditor", function() {
            // Have to fire editor after snippets, if snippets enabled
            if (StackExchange.settings.snippets.snippetsEnabled) {
            StackExchange.using("snippets", function() {
            createEditor();
            });
            }
            else {
            createEditor();
            }
            });

            function createEditor() {
            StackExchange.prepareEditor({
            heartbeatType: 'answer',
            autoActivateHeartbeat: false,
            convertImagesToLinks: false,
            noModals: true,
            showLowRepImageUploadWarning: true,
            reputationToPostImages: null,
            bindNavPrevention: true,
            postfix: "",
            imageUploader: {
            brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
            contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
            allowUrls: true
            },
            onDemand: true,
            discardSelector: ".discard-answer"
            ,immediatelyShowMarkdownHelp:true
            });


            }
            });














            draft saved

            draft discarded


















            StackExchange.ready(
            function () {
            StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fdatascience.stackexchange.com%2fquestions%2f17679%2fr-caret-does-caret-automatically-create-dummy-variable-for-random-forest%23new-answer', 'question_page');
            }
            );

            Post as a guest















            Required, but never shown

























            1 Answer
            1






            active

            oldest

            votes








            1 Answer
            1






            active

            oldest

            votes









            active

            oldest

            votes






            active

            oldest

            votes









            0












            $begingroup$

            Yes, it does for some models. You can inspect which variables are used via
            model$coefnames.






            share|improve this answer








            New contributor




            Marcus Lauritsen is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
            Check out our Code of Conduct.






            $endgroup$


















              0












              $begingroup$

              Yes, it does for some models. You can inspect which variables are used via
              model$coefnames.






              share|improve this answer








              New contributor




              Marcus Lauritsen is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
              Check out our Code of Conduct.






              $endgroup$
















                0












                0








                0





                $begingroup$

                Yes, it does for some models. You can inspect which variables are used via
                model$coefnames.






                share|improve this answer








                New contributor




                Marcus Lauritsen is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
                Check out our Code of Conduct.






                $endgroup$



                Yes, it does for some models. You can inspect which variables are used via
                model$coefnames.







                share|improve this answer








                New contributor




                Marcus Lauritsen is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
                Check out our Code of Conduct.









                share|improve this answer



                share|improve this answer






                New contributor




                Marcus Lauritsen is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
                Check out our Code of Conduct.









                answered 12 mins ago









                Marcus LauritsenMarcus Lauritsen

                1




                1




                New contributor




                Marcus Lauritsen is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
                Check out our Code of Conduct.





                New contributor





                Marcus Lauritsen is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
                Check out our Code of Conduct.






                Marcus Lauritsen is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
                Check out our Code of Conduct.






























                    draft saved

                    draft discarded




















































                    Thanks for contributing an answer to Data Science Stack Exchange!


                    • Please be sure to answer the question. Provide details and share your research!

                    But avoid



                    • Asking for help, clarification, or responding to other answers.

                    • Making statements based on opinion; back them up with references or personal experience.


                    Use MathJax to format equations. MathJax reference.


                    To learn more, see our tips on writing great answers.




                    draft saved


                    draft discarded














                    StackExchange.ready(
                    function () {
                    StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fdatascience.stackexchange.com%2fquestions%2f17679%2fr-caret-does-caret-automatically-create-dummy-variable-for-random-forest%23new-answer', 'question_page');
                    }
                    );

                    Post as a guest















                    Required, but never shown





















































                    Required, but never shown














                    Required, but never shown












                    Required, but never shown







                    Required, but never shown

































                    Required, but never shown














                    Required, but never shown












                    Required, but never shown







                    Required, but never shown







                    Popular posts from this blog

                    How to label and detect the document text images

                    Vallis Paradisi

                    Tabula Rosettana