interpreting simple slopes even if interaction effect is not significant?

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interpreting simple slopes even if interaction effect is not significant?

psy_vm
Hello,

Can we interpret simple slopes or Johnson-Neyman even if our interaction effect is not significant? If yes, then how? Also, what do we do with Data for visualizing conditional effect of X on Y?
My results are listed below. Thanks in advance!

*********.
Model = 1
    Y = qoltot
    X = VisaGrou
    M = bcope_ma

Sample size
         97

**************************************************************************
Outcome: qoltot

Model Summary
          R       R-sq          F        df1        df2          p
      .5083      .2584    10.9638     3.0000    93.0000      .0000

Model
              coeff         se          t          p       LLCI       ULCI
constant    68.8666     1.7854    38.5717      .0000    65.3211    72.4121
bcope_ma     -.7737      .3217    -2.4048      .0182    -1.4125     -.1348
VisaGrou   -12.1130     3.5872    -3.3767      .0011   -19.2366    -4.9895
int_1        1.0766      .6546     1.6445      .1034     -.2234     2.3765

Interactions:

 int_1    VisaGrou    X     bcope_ma

*************************************************************************

Conditional effect of X on Y at values of the moderator(s):
   bcope_ma     Effect         se          t          p       LLCI       ULCI
    -5.9635   -18.5331     4.8543    -3.8179      .0002   -28.1727    -8.8934
      .0000   -12.1130     3.5872    -3.3767      .0011   -19.2366    -4.9895
     5.9635    -5.6930     5.7143     -.9963      .3217   -17.0406     5.6546

Values for quantitative moderators are the mean and plus/minus one SD from mean.
Values for dichotomous moderators are the two values of the moderator.

********************* JOHNSON-NEYMAN TECHNIQUE **************************

Moderator value(s) defining Johnson-Neyman significance region(s):
      Value    % below    % above
     3.1219    71.1340    28.8660

Conditional effect of X on Y at values of the moderator (M)
   bcope_ma     Effect         se          t          p       LLCI       ULCI
    -8.7526   -21.5357     6.2472    -3.4472      .0009   -33.9415    -9.1299
    -7.5526   -20.2438     5.6176    -3.6037      .0005   -31.3993    -9.0884
    -6.3526   -18.9520     5.0320    -3.7663      .0003   -28.9445    -8.9594
    -5.1526   -17.6601     4.5077    -3.9178      .0002   -26.6114    -8.7088
    -3.9526   -16.3682     4.0683    -4.0234      .0001   -24.4471    -8.2893
    -2.7526   -15.0763     3.7440    -4.0268      .0001   -22.5112    -7.6415
    -1.5526   -13.7845     3.5662    -3.8653      .0002   -20.8663    -6.7026
     -.3526   -12.4926     3.5571    -3.5120      .0007   -19.5563    -5.4289
      .8474   -11.2007     3.7178    -3.0127      .0033   -18.5835    -3.8179
     2.0474    -9.9089     4.0280    -2.4600      .0157   -17.9078    -1.9099
     3.1219    -8.7521     4.4073    -1.9858      .0500   -17.5041      .0000
     3.2474    -8.6170     4.4567    -1.9335      .0562   -17.4672      .2333
     4.4474    -7.3251     4.9734    -1.4729      .1442   -17.2012     2.5510
     5.6474    -6.0332     5.5534    -1.0864      .2801   -17.0612     4.9947
     6.8474    -4.7414     6.1790     -.7673      .4448   -17.0117     7.5290
     8.0474    -3.4495     6.8377     -.5045      .6151   -17.0279    10.1289
     9.2474    -2.1576     7.5208     -.2869      .7748   -17.0926    12.7773
    10.4474     -.8657     8.2223     -.1053      .9164   -17.1936    15.4621
    11.6474      .4261     8.9377      .0477      .9621   -17.3225    18.1747
    12.8474     1.7180     9.6641      .1778      .8593   -17.4730    20.9090
    14.0474     3.0099    10.3990      .2894      .7729   -17.6406    23.6603
    15.2474     4.3017    11.1409      .3861      .7003   -17.8219    26.4254

**************************************************************************

Data for visualizing conditional effect of X on Y:
   VisaGrou   bcope_ma       yhat
     -.5464    -5.9635    83.6066
      .4536    -5.9635    65.0736
     -.5464      .0000    75.4850
      .4536      .0000    63.3720
     -.5464     5.9635    67.3635
      .4536     5.9635    61.6705

******************** ANALYSIS NOTES AND WARNINGS *************************

Level of confidence for all confidence intervals in output:
    95.00

NOTE: The following variables were mean centered prior to analysis:
 VisaGrou bcope_ma

NOTE: Some cases were deleted due to missing data.  The number of such cases was:
  6

NOTE: All standard errors for continuous outcome models are based on the HC3 estimator

------ END MATRIX -----
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Re: interpreting simple slopes even if interaction effect is not significant?

David Marso
Administrator
What does this question have to do with SPSS?
That is not standard SPSS output (aside that somebodies macro spit it out of MATRIX).
Off hand I would say NO.  If the effect is NOT sig then you shouldn't be fishing around in the dung looking for a pearl.

psy_vm wrote
Hello,

Can we interpret simple slopes or Johnson-Neyman even if our interaction effect is not significant? If yes, then how? Also, what do we do with Data for visualizing conditional effect of X on Y?
My results are listed below. Thanks in advance!

*********.
Model = 1
    Y = qoltot
    X = VisaGrou
    M = bcope_ma

Sample size
         97

**************************************************************************
Outcome: qoltot

Model Summary
          R       R-sq          F        df1        df2          p
      .5083      .2584    10.9638     3.0000    93.0000      .0000

Model
              coeff         se          t          p       LLCI       ULCI
constant    68.8666     1.7854    38.5717      .0000    65.3211    72.4121
bcope_ma     -.7737      .3217    -2.4048      .0182    -1.4125     -.1348
VisaGrou   -12.1130     3.5872    -3.3767      .0011   -19.2366    -4.9895
int_1        1.0766      .6546     1.6445      .1034     -.2234     2.3765

Interactions:

 int_1    VisaGrou    X     bcope_ma

*************************************************************************

Conditional effect of X on Y at values of the moderator(s):
   bcope_ma     Effect         se          t          p       LLCI       ULCI
    -5.9635   -18.5331     4.8543    -3.8179      .0002   -28.1727    -8.8934
      .0000   -12.1130     3.5872    -3.3767      .0011   -19.2366    -4.9895
     5.9635    -5.6930     5.7143     -.9963      .3217   -17.0406     5.6546

Values for quantitative moderators are the mean and plus/minus one SD from mean.
Values for dichotomous moderators are the two values of the moderator.

********************* JOHNSON-NEYMAN TECHNIQUE **************************

Moderator value(s) defining Johnson-Neyman significance region(s):
      Value    % below    % above
     3.1219    71.1340    28.8660

Conditional effect of X on Y at values of the moderator (M)
   bcope_ma     Effect         se          t          p       LLCI       ULCI
    -8.7526   -21.5357     6.2472    -3.4472      .0009   -33.9415    -9.1299
    -7.5526   -20.2438     5.6176    -3.6037      .0005   -31.3993    -9.0884
    -6.3526   -18.9520     5.0320    -3.7663      .0003   -28.9445    -8.9594
    -5.1526   -17.6601     4.5077    -3.9178      .0002   -26.6114    -8.7088
    -3.9526   -16.3682     4.0683    -4.0234      .0001   -24.4471    -8.2893
    -2.7526   -15.0763     3.7440    -4.0268      .0001   -22.5112    -7.6415
    -1.5526   -13.7845     3.5662    -3.8653      .0002   -20.8663    -6.7026
     -.3526   -12.4926     3.5571    -3.5120      .0007   -19.5563    -5.4289
      .8474   -11.2007     3.7178    -3.0127      .0033   -18.5835    -3.8179
     2.0474    -9.9089     4.0280    -2.4600      .0157   -17.9078    -1.9099
     3.1219    -8.7521     4.4073    -1.9858      .0500   -17.5041      .0000
     3.2474    -8.6170     4.4567    -1.9335      .0562   -17.4672      .2333
     4.4474    -7.3251     4.9734    -1.4729      .1442   -17.2012     2.5510
     5.6474    -6.0332     5.5534    -1.0864      .2801   -17.0612     4.9947
     6.8474    -4.7414     6.1790     -.7673      .4448   -17.0117     7.5290
     8.0474    -3.4495     6.8377     -.5045      .6151   -17.0279    10.1289
     9.2474    -2.1576     7.5208     -.2869      .7748   -17.0926    12.7773
    10.4474     -.8657     8.2223     -.1053      .9164   -17.1936    15.4621
    11.6474      .4261     8.9377      .0477      .9621   -17.3225    18.1747
    12.8474     1.7180     9.6641      .1778      .8593   -17.4730    20.9090
    14.0474     3.0099    10.3990      .2894      .7729   -17.6406    23.6603
    15.2474     4.3017    11.1409      .3861      .7003   -17.8219    26.4254

**************************************************************************

Data for visualizing conditional effect of X on Y:
   VisaGrou   bcope_ma       yhat
     -.5464    -5.9635    83.6066
      .4536    -5.9635    65.0736
     -.5464      .0000    75.4850
      .4536      .0000    63.3720
     -.5464     5.9635    67.3635
      .4536     5.9635    61.6705

******************** ANALYSIS NOTES AND WARNINGS *************************

Level of confidence for all confidence intervals in output:
    95.00

NOTE: The following variables were mean centered prior to analysis:
 VisaGrou bcope_ma

NOTE: Some cases were deleted due to missing data.  The number of such cases was:
  6

NOTE: All standard errors for continuous outcome models are based on the HC3 estimator

------ END MATRIX -----
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