https://communities.sas.com/t5/SAS-Programming/Proc-GLM-WELCH-one-tailed-test/m-p/881673#M348376 <P>Hi! I am using the proc glm welch option in order to implement a welch anova analysis. Is this test one-tailed or two-tailed?</P><P>This is the type of code i am using:</P><PRE>proc glm; class trt; model y = trt; means trt / hovtest=levene welch; run;</PRE><P>Thank you!&nbsp;</P> Wed, 21 Jun 2023 11:05:02 GMT User423350 2023-06-21T11:05:02Z https://communities.sas.com/t5/SAS-Programming/Proc-GLM-WELCH-one-tailed-test/m-p/881673#M348376 <P>Hi! I am using the proc glm welch option in order to implement a welch anova analysis. Is this test one-tailed or two-tailed?</P><P>This is the type of code i am using:</P><PRE>proc glm; class trt; model y = trt; means trt / hovtest=levene welch; run;</PRE><P>Thank you!&nbsp;</P> Wed, 21 Jun 2023 11:05:02 GMT https://communities.sas.com/t5/SAS-Programming/Proc-GLM-WELCH-one-tailed-test/m-p/881673#M348376 User423350 2023-06-21T11:05:02Z https://communities.sas.com/t5/SAS-Programming/Proc-GLM-WELCH-one-tailed-test/m-p/881677#M348379 <P>I think this is a two-sided test, as are all tests in ANOVA.</P> Wed, 21 Jun 2023 11:16:57 GMT https://communities.sas.com/t5/SAS-Programming/Proc-GLM-WELCH-one-tailed-test/m-p/881677#M348379 PaigeMiller 2023-06-21T11:16:57Z https://communities.sas.com/t5/SAS-Programming/Proc-GLM-WELCH-one-tailed-test/m-p/881678#M348380 How can i make the test one-tailed? Wed, 21 Jun 2023 11:18:22 GMT https://communities.sas.com/t5/SAS-Programming/Proc-GLM-WELCH-one-tailed-test/m-p/881678#M348380 User423350 2023-06-21T11:18:22Z