I am trying to analyse my regression results and I need to interpret the economic magnitude of specific independent variable in terms of its standard deviation.
For example: Y = a + bX + u
In general, one can say that when X increases by one unit, Y is expected to increase by 'b' value.
Alternatively, one can say that when X increases by one standard deviation, Y is expected to increase by 'some' value.
How to obtain this 'some' value in SAS?
To my understanding, formulary, for std change in X, Y would change : [b*std(y)] / mean(y). I am not sure if this formula is correct.
If N is the number of SD from the mean of X wouldn't you want:
a + bX* (meanX+N*sdX)
?
an Example:
data have; input x y; cards; 1 3 2 6 3 9 4 12 5 14 6 18 7 20 8 24 9 26 10 28 ; proc reg data=have; model Y=X; run; proc means data=have; var x y; run;
results in: MeanX=5.5 sdX=3.02765 bX=2.83636 a=.4
Thus, 2 sd above mean would be x=11.5553
.4 +2.83636*11.553=33.17499
Art, CEO, AnalystFinder.com
Alternatively, one can say that when X increases by one standard deviation, Y is expected to increase by 'some' value.
How to obtain this 'some' value in SAS?
Y increases by b * (one standard deviation of X)
Join us for SAS Innovate 2025, our biggest and most exciting global event of the year, in Orlando, FL, from May 6-9. Sign up by March 14 for just $795.
ANOVA, or Analysis Of Variance, is used to compare the averages or means of two or more populations to better understand how they differ. Watch this tutorial for more.
Find more tutorials on the SAS Users YouTube channel.