Hi I need help in intepreting interaction terms after running a fixed-effect model regression.
Here is my regression code and thereafter the output:
What I dont fully grasp is how to interpret the interaction terms. First i conclude that, for example that the interaction ECL#c.BVEBLLPS is not significant but ECL#c.CLPS is. My intepretation of this is that ECL has a significant impact on CLPS but not on BVEBLLPS.
However I've been trying to understand how to inteperet interaction and have come across a lot of article which mentions having to run -margins- to fully understand interaction effects. If i run, for example:
i get the following output:
and my conclusion of this is that BVEBLLPS is statistically significant under either ECL=1 or ECL=0 but can the coefficients be compared? I see that dydx for ECL=1 is smaller than under ECL=0, does this indicate that BVEBLLPS has a lesser impact when ECL=1 or what interpretations can one make of this? Again, ECL#BVEBLLPS was not significant to start with.
I apologize if i have misstated anything in regards to forum manners, this is my first post.
Here is my regression code and thereafter the output:
Code:
xtreg SP_3m i.ECL##c.(BVEBLLPS EBCLPS CLPS LLPS) trend, fe vce(cluster C_ID)
Code:
Fixed-effects (within) regression Number of obs = 3,847 Group variable: C_ID Number of groups = 163 R-sq: Obs per group: within = 0.4212 min = 1 between = 0.5445 avg = 23.6 overall = 0.4241 max = 44 F(10,162) = 11.99 corr(u_i, Xb) = 0.0817 Prob > F = 0.0000 (Std. Err. adjusted for 163 clusters in C_ID) -------------------------------------------------------------------------------- | Robust SP_3m | Coef. Std. Err. t P>|t| [95% Conf. Interval] ---------------+---------------------------------------------------------------- 1.ECL | -.9309141 .8287776 -1.12 0.263 -2.567514 .7056861 BVEBLLPS | .3881563 .0830101 4.68 0.000 .2242349 .5520777 EBCLPS | 2.771403 .9288563 2.98 0.003 .9371753 4.60563 CLPS | -4.081289 2.029158 -2.01 0.046 -8.088301 -.0742781 LLPS | -.5309146 .2554378 -2.08 0.039 -1.035332 -.0264975 | ECL#c.BVEBLLPS | 1 | -.0368249 .042226 -0.87 0.384 -.1202092 .0465594 | ECL#c.EBCLPS | 1 | 1.731694 1.257783 1.38 0.170 -.75207 4.215458 | ECL#c.CLPS | 1 | -6.616726 2.481017 -2.67 0.008 -11.51603 -1.717423 | ECL#c.LLPS | 1 | -.4354413 .1637303 -2.66 0.009 -.7587622 -.1121204 | trend | .0803695 .0436028 1.84 0.067 -.0057337 .1664726 _cons | 5.063715 1.490964 3.40 0.001 2.119484 8.007946 ---------------+---------------------------------------------------------------- sigma_u | 12.088387 sigma_e | 5.3343022 rho | .8370137 (fraction of variance due to u_i) --------------------------------------------------------------------------------
However I've been trying to understand how to inteperet interaction and have come across a lot of article which mentions having to run -margins- to fully understand interaction effects. If i run, for example:
Code:
margins ECL, dydx(BVEBLLPS)
Code:
Average marginal effects Number of obs = 3,847 Model VCE : Robust Expression : Linear prediction, predict() dy/dx w.r.t. : BVEBLLPS ------------------------------------------------------------------------------ | Delta-method | dy/dx Std. Err. z P>|z| [95% Conf. Interval] -------------+---------------------------------------------------------------- BVEBLLPS | ECL | 0 | .3881563 .0830101 4.68 0.000 .2254594 .5508531 1 | .3513314 .0706185 4.98 0.000 .2129218 .489741 ------------------------------------------------------------------------------
I apologize if i have misstated anything in regards to forum manners, this is my first post.
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