https://communities.sas.com/t5/SAS-Data-Science/In-SAS-EM-how-can-I-know-which-one-is-the-base-level-for-nominal/m-p/772916#M8913 Thanks. Fri, 08 Oct 2021 01:08:12 GMT ycenycute 2021-10-08T01:08:12Z https://communities.sas.com/t5/SAS-Data-Science/In-SAS-EM-how-can-I-know-which-one-is-the-base-level-for-nominal/m-p/772085#M8905 <P>In SAS EM, if you specify a variable as a nominal variable, then in the regression results, it will automatically drop one value as the base level. How can I check which value the software dropped after I run the analysis?</P> Tue, 05 Oct 2021 08:06:54 GMT https://communities.sas.com/t5/SAS-Data-Science/In-SAS-EM-how-can-I-know-which-one-is-the-base-level-for-nominal/m-p/772085#M8905 ycenycute 2021-10-05T08:06:54Z https://communities.sas.com/t5/SAS-Data-Science/In-SAS-EM-how-can-I-know-which-one-is-the-base-level-for-nominal/m-p/772220#M8906 <P>SAS EM&nbsp; uses the last level as the reference level after sorting the nominal variable alphabetically.</P> Tue, 05 Oct 2021 16:39:25 GMT https://communities.sas.com/t5/SAS-Data-Science/In-SAS-EM-how-can-I-know-which-one-is-the-base-level-for-nominal/m-p/772220#M8906 gcjfernandez 2021-10-05T16:39:25Z https://communities.sas.com/t5/SAS-Data-Science/In-SAS-EM-how-can-I-know-which-one-is-the-base-level-for-nominal/m-p/772325#M8907 Thank you. Is there a way we can change this or choose the base level on our own? Wed, 06 Oct 2021 00:16:29 GMT https://communities.sas.com/t5/SAS-Data-Science/In-SAS-EM-how-can-I-know-which-one-is-the-base-level-for-nominal/m-p/772325#M8907 ycenycute 2021-10-06T00:16:29Z https://communities.sas.com/t5/SAS-Data-Science/In-SAS-EM-how-can-I-know-which-one-is-the-base-level-for-nominal/m-p/772339#M8908 <P>You could recode the level you want to use as the baseline by adding 'z' in front of the current level. In SAS EM you can do this using the replacement node- select the nominal variable editor and specify your modified levels.</P> Wed, 06 Oct 2021 04:16:28 GMT https://communities.sas.com/t5/SAS-Data-Science/In-SAS-EM-how-can-I-know-which-one-is-the-base-level-for-nominal/m-p/772339#M8908 gcjfernandez 2021-10-06T04:16:28Z https://communities.sas.com/t5/SAS-Data-Science/In-SAS-EM-how-can-I-know-which-one-is-the-base-level-for-nominal/m-p/772397#M8909 Got you. Thanks so much. Also wondering if I manually create dummy indicators for categorical variable, then I can choose to drop one dummy as the base level. Then when I include the rest dummy indicators in the model, the results show 0 behind the name of the dummy indicator. Does this mean the coefficient is for dummy _indicator = 0? This is quite counter-intuitive to me. How does SAS EM treat dummy indicators when running regression? Wed, 06 Oct 2021 11:01:49 GMT https://communities.sas.com/t5/SAS-Data-Science/In-SAS-EM-how-can-I-know-which-one-is-the-base-level-for-nominal/m-p/772397#M8909 ycenycute 2021-10-06T11:01:49Z https://communities.sas.com/t5/SAS-Data-Science/In-SAS-EM-how-can-I-know-which-one-is-the-base-level-for-nominal/m-p/772578#M8910 <P>When you create a dummy variable with 0 and 1, by default level I will be assigned as the base line and 0 versus I tested.</P> <P>&nbsp;</P> <P>Therefore&nbsp; when creating the dummy variable, assign the level of interest to 0 and reference level to 1.</P> <P>&nbsp;</P> <P>&nbsp;</P> Wed, 06 Oct 2021 21:15:41 GMT https://communities.sas.com/t5/SAS-Data-Science/In-SAS-EM-how-can-I-know-which-one-is-the-base-level-for-nominal/m-p/772578#M8910 gcjfernandez 2021-10-06T21:15:41Z https://communities.sas.com/t5/SAS-Data-Science/In-SAS-EM-how-can-I-know-which-one-is-the-base-level-for-nominal/m-p/772603#M8911 I mean I manually create four dummy indicators for a categorical variable with 4 categories, then I drop one of the dummy indicator as the base level. But when I include the rest 3 dummy indicators in the model, how do those dummies work? By default, they are 1 for yes, 0 for no, but it seems to show the coefficient for 0. Are you suggesting I should set 1 for no and 0 for yes? If so, how shall I change that? Thu, 07 Oct 2021 00:24:59 GMT https://communities.sas.com/t5/SAS-Data-Science/In-SAS-EM-how-can-I-know-which-one-is-the-base-level-for-nominal/m-p/772603#M8911 ycenycute 2021-10-07T00:24:59Z https://communities.sas.com/t5/SAS-Data-Science/In-SAS-EM-how-can-I-know-which-one-is-the-base-level-for-nominal/m-p/772630#M8912 <P>You need to recreate the dummy variables (where assign 0 to yes and 1 to NO) in a data step.</P> <P>Because by default between 0 and 1, 1 will be assigned to base level.</P> <P>&nbsp;</P> <P>Other option: If you can substitute the HPGLM node for the Reg node, then you can specify the class level you want to specify as the base level in the properties.</P> Thu, 07 Oct 2021 05:47:03 GMT https://communities.sas.com/t5/SAS-Data-Science/In-SAS-EM-how-can-I-know-which-one-is-the-base-level-for-nominal/m-p/772630#M8912 gcjfernandez 2021-10-07T05:47:03Z https://communities.sas.com/t5/SAS-Data-Science/In-SAS-EM-how-can-I-know-which-one-is-the-base-level-for-nominal/m-p/772916#M8913 Thanks. Fri, 08 Oct 2021 01:08:12 GMT https://communities.sas.com/t5/SAS-Data-Science/In-SAS-EM-how-can-I-know-which-one-is-the-base-level-for-nominal/m-p/772916#M8913 ycenycute 2021-10-08T01:08:12Z