# Reporting estimates in mixed models

this may be a stupid question, but I have run a mixed effects model in R and the estimates, Standard Error and dfs are are all numbers such as -2.115e-01. I've only seen these in p-values before and I'm not sure to report them when they have no clear relationbship to the original scale (Bark scale ranging from -4 to +2). What is the best way to discuss these findings?

Thanks

tryskew8 = lmer(skewness~ respondent + respondent : duration+ (1|word) + (1|video), REML = F , clean)
summary(tryskew8)

Fixed effects:
Estimate Std. Error         df t value Pr(>|t|)
(Intercept)                    -2.115e-01  1.775e-01  3.844e+01  -1.192 0.240738
respondentgay.referee          -4.270e-01  2.876e-01  4.355e+01  -1.485 0.144834
respondentcoming.out           -1.412e+00  3.111e-01  2.465e+01  -4.538 0.000127 ***
respondentout                  -7.549e-01  3.069e-01  2.335e+01  -2.460 0.021703 *
respondentphil.in:duration      3.125e-04  1.411e-03  3.823e+02   0.222 0.824788
respondentgay.referee:duration -2.118e-03  1.950e-03  3.873e+02  -1.086 0.277937
respondentcoming.out:duration   2.144e-03  1.837e-03  3.832e+02   1.167 0.243932
respondentout:duration          2.449e-03  1.626e-03  3.769e+02   1.506 0.132956

• Your significant effects are not that small compared to a range from -4 to 2, are they? – jay.sf May 24 at 17:48
• Maybe it's just that the scientific notation is crossing you up. "-2.115e-01" indicates -0.2115: just move the decimal point left (if "-") or right (if "+") the number of places indicated after the "e". You can also set R to avoid that notation -- stackoverflow.com/questions/9397664/…. – rolando2 May 24 at 18:10
• Your model seems to include an interaction term involving duration without a corresponding term for duration on its own. That's almost never a good idea, and can affect the values and interpretations of the interaction coefficients. See this page for example. Also, think carefully about your choice to use maximum likelihood instead of REML for fitting for model to the data unless you have a very large study. – EdM May 24 at 18:12
• Excellent, thanks very much! Now the scientific notation makes sense, I've also added a term for duration to the model – Brad May 26 at 11:08