topic Comparing slope of two regression lines in Statistical Procedures https://communities.sas.com/t5/Statistical-Procedures/Comparing-slope-of-two-regression-lines/m-p/49270#M2190 <HTML><HEAD></HEAD><BODY><P>I want to determine if the the response to one treatment is different from another.&nbsp; I have multiple animals, some that received drug A and others drug B.&nbsp; They are distrubuted based on starting weight, so the x-axis is a continuous variable.&nbsp; The y-axis is response time in seconds.&nbsp; Essentially I would like to determine whether the slopes of the best fit lines are similiar or different.&nbsp;&nbsp;&nbsp;&nbsp; </P></BODY></HTML> Tue, 16 Aug 2011 17:25:27 GMT MattK 2011-08-16T17:25:27Z Comparing slope of two regression lines https://communities.sas.com/t5/Statistical-Procedures/Comparing-slope-of-two-regression-lines/m-p/49270#M2190 <HTML><HEAD></HEAD><BODY><P>I want to determine if the the response to one treatment is different from another.&nbsp; I have multiple animals, some that received drug A and others drug B.&nbsp; They are distrubuted based on starting weight, so the x-axis is a continuous variable.&nbsp; The y-axis is response time in seconds.&nbsp; Essentially I would like to determine whether the slopes of the best fit lines are similiar or different.&nbsp;&nbsp;&nbsp;&nbsp; </P></BODY></HTML> Tue, 16 Aug 2011 17:25:27 GMT https://communities.sas.com/t5/Statistical-Procedures/Comparing-slope-of-two-regression-lines/m-p/49270#M2190 MattK 2011-08-16T17:25:27Z Re: Comparing slope and intercept of two lines https://communities.sas.com/t5/Statistical-Procedures/Comparing-slope-of-two-regression-lines/m-p/49271#M2191 <HTML><HEAD></HEAD><BODY><P>build a linear model y= intercept+x+trt +x*trt and then test the coefficient for x*trt to see if the slopes are zero. to test if both treatments have the same intercept then test the trt coefficient to see if it zero.</P></BODY></HTML> Tue, 16 Aug 2011 18:09:36 GMT https://communities.sas.com/t5/Statistical-Procedures/Comparing-slope-of-two-regression-lines/m-p/49271#M2191 trekvana 2011-08-16T18:09:36Z Comparing slope of two regression lines https://communities.sas.com/t5/Statistical-Procedures/Comparing-slope-of-two-regression-lines/m-p/49272#M2192 <HTML><HEAD></HEAD><BODY><P>Is there not a way to perform this analysis without writing script?</P></BODY></HTML> Tue, 16 Aug 2011 18:35:20 GMT https://communities.sas.com/t5/Statistical-Procedures/Comparing-slope-of-two-regression-lines/m-p/49272#M2192 MattK 2011-08-16T18:35:20Z Comparing slope of two regression lines https://communities.sas.com/t5/Statistical-Procedures/Comparing-slope-of-two-regression-lines/m-p/49273#M2193 <HTML><HEAD></HEAD><BODY><P>you can do it in the point-n-click interface of Enterprise Guide.</P></BODY></HTML> Tue, 16 Aug 2011 19:24:35 GMT https://communities.sas.com/t5/Statistical-Procedures/Comparing-slope-of-two-regression-lines/m-p/49273#M2193 Doc_Duke 2011-08-16T19:24:35Z