tag:blogger.com,1999:blog-7958828565254404797.post9141360271592290028..comments2020-01-24T23:57:25.710-08:00Comments on ListenData: Chi-Square : Variable Reduction TechniqueDeepanshu Bhallahttp://www.blogger.com/profile/09802839558125192674noreply@blogger.comBlogger8125tag:blogger.com,1999:blog-7958828565254404797.post-2270598082123200462018-06-02T20:59:09.014-07:002018-06-02T20:59:09.014-07:00Hi Sir, do you have another chapter which deals wi...Hi Sir, do you have another chapter which deals with feature selection of categorical variable using chi square test in R?<br />Aayushhttps://www.blogger.com/profile/07656102737219402631noreply@blogger.comtag:blogger.com,1999:blog-7958828565254404797.post-81779590510910553602015-05-14T09:04:29.053-07:002015-05-14T09:04:29.053-07:00Ok. Changd now. Thanks for that. I guess the same ...Ok. Changd now. Thanks for that. I guess the same process goes for categorical variables using proc freq?izyk nietinoreply@blogger.comtag:blogger.com,1999:blog-7958828565254404797.post-25271188374328480042015-05-14T08:15:42.266-07:002015-05-14T08:15:42.266-07:00I would request you to post your question as an id...I would request you to post your question as an identified user. I don't want to encourage readers post comments as "Anonymous". Thanks!Deepanshu Bhallahttps://www.blogger.com/profile/09802839558125192674noreply@blogger.comtag:blogger.com,1999:blog-7958828565254404797.post-74502480599241300372015-05-14T08:12:03.700-07:002015-05-14T08:12:03.700-07:00Step 1 : Run logistic regression on each of the in...Step 1 : Run logistic regression on each of the independent variable and selecting all the variables having p-value less than 0.25. For example, you have 10 independent variables, so run UNIVARIATE logistic regression 10 times for each of the variable and recording their p-values.<br /><br />Step 2 : Run multivariate logistic regression on all the variables selecting at step 1 and now set p-value 0.05.Deepanshu Bhallahttps://www.blogger.com/profile/09802839558125192674noreply@blogger.comtag:blogger.com,1999:blog-7958828565254404797.post-74453529094975567102015-05-14T06:58:29.952-07:002015-05-14T06:58:29.952-07:00Pls i posted questions under the following topics:...Pls i posted questions under the following topics: model validation, scoring in logistic, bootstrapping. <br /><br />tnxAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-7958828565254404797.post-83674954989158224602015-05-14T06:21:13.640-07:002015-05-14T06:21:13.640-07:00ok u mean running the logistic regression with no ...ok u mean running the logistic regression with no selection options and viewing p-values of each variable before seeting p-value...but not more than 0.25?Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-7958828565254404797.post-40812962114517713942015-05-14T05:02:04.499-07:002015-05-14T05:02:04.499-07:00Use of conservative sig level (0.05) often leads t...Use of conservative sig level (0.05) often leads to important variables excluded from analysis. It is recommended to use higher level based on the work by Mickey and Greenland (1989) on logistic regression. It is important to CHECK the IMPORTANCE of these variables in multivariable model stage before deciding your final variables.Deepanshu Bhallahttps://www.blogger.com/profile/09802839558125192674noreply@blogger.comtag:blogger.com,1999:blog-7958828565254404797.post-9772071212381123462015-05-13T16:34:44.287-07:002015-05-13T16:34:44.287-07:00Why 0.25 and not 0.05?Why 0.25 and not 0.05?Anonymousnoreply@blogger.com