anova() does not display p-value when used with lmerTest
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I'm trying to use lmerTest to have p-values for my fixed effects. I have 4 different random intercepts, 3 crossed and one nested :

test.reml <- lmerTest::lmer(y ~   s1 + min + cot +  min:cot + ge 
+ vis + dur + mo + nps + dist + st1 + st2 + di1 + s1:cot 
+ s1:min + s1:cot:min + s1:ge + s1:vis + s1:dur + s1:mo 
+ s1:nps + s1:dist + s1:st1 + s1:st2 + s1:di1 +  (1|Unique_key)
+ (s1-1|object) + (ns1-1|object) 
+ (1|region), bdr, REML=1)

The objects are observed two times and the correlation between the two measures is introduced by the random effect on Unique_key, an unique identifier of the object i in a region j. Each object could be observed in any region. S1 is a binary variable that takes the value 1 if the observation is observed the first time period and 0 either. There is one random intercept for the first periode and one random intercept for the second period for each object. ns1 is in fact a binary variable that is the complement of s1 and s1 + ns1 = 1 for each observation.

I can fit the model and get the estimates and p-values with summary() :

    summary( test.reml)
Linear mixed model fit by REML ['merModLmerTest']
Formula: y ~   s1 + min + cot +  min:cot + ge 
    + vis + dur + mo + nps + dist + st1 + st2 + di1 + s1:cot 
    + s1:min + s1:cot:min + s1:ge + s1:vis + s1:dur + s1:mo 
    + s1:nps + s1:dist + s1:st1 + s1:st2 + s1:di1 +  (1|Unique_key)
    + (s1-1|object) + (ns1-1|object) 
    + (1|region), bdr, REML=1) 
   Data: bdr 

REML criterion at convergence: 204569.1 

Random effects:
 Groups     Name        Variance Std.Dev.
 Unique_key (Intercept) 0.2023   0.4497  
 object    s1           0.3528   0.5940  
 object.1  ns1         0.5954   0.7716  
 Region     (Intercept) 0.7563   0.8697  
 Residual               0.1795   0.4237  
Number of obs: 113396, groups: Unique_key , 58541; object, 1065; Region, 87

Fixed effects:
                    Estimate Std. Error t value Pr(>|t|)    
(Intercept)        6.7341569  0.2382673  28.263  < 2e-16 ***
s1                 0.7391924  0.2004413   3.688 0.000233 ***
min               -0.0067606  0.0171385  -0.394 0.694205    
cot                0.1235093  0.0353693   3.492 0.000499 ***
ge2               -0.1535452  0.0800998  -1.917 0.055525 .  
ge3               -0.2131246  0.0986559  -2.160 0.030982 *  
ge4               -0.1032694  0.1115603  -0.926 0.354830    
ge5               -0.1769347  0.1296558  -1.365 0.172663    
ge6                0.0117401  0.1115897   0.105 0.916231    
ge7               -0.2692483  0.1022565  -2.633 0.008589 ** 
vis2              -0.0928661  0.0607950  -1.528 0.126938    
vis3              -0.3026112  0.1246595  -2.428 0.015375 *  
dur2               0.1479195  0.0786369   1.881 0.060249 .  
dur3               0.1406340  0.0809379   1.738 0.082590 .  
dur4               0.2742243  0.0884301   3.101 0.001981 ** 
dur5               0.1946761  0.1065815   1.827 0.068059 .  
mo2               -0.1168591  0.1256017  -0.930 0.352386    
mo3               -0.0611162  0.1267657  -0.482 0.629824    
mo4               -0.2725720  0.1263740  -2.157 0.031248 *  
mo5               -0.6107000  0.1379264  -4.428 1.05e-05 ***
mo6               -0.3635142  0.1299799  -2.797 0.005260 ** 
mo7               -0.0899233  0.1275164  -0.705 0.480846    
mo8               -0.2349548  0.1253422  -1.875 0.061140 .  
mo9               -0.2624888  0.1263051  -2.078 0.037934 *  
mo10              -0.2882749  0.1244404  -2.317 0.020724 *  
mo11              -0.1702823  0.1356031  -1.256 0.209497    
mo12               0.1989155  0.1322339   1.504 0.132819    
nps                0.0278418  0.0010393  26.790  < 2e-16 ***
dist2              0.4065093  0.1118916   3.633 0.000294 ***
dist3              0.0155691  0.0906664   0.172 0.863693    
dist4             -0.2910960  0.1595805  -1.824 0.068424 .  
dist5             -0.1316553  0.0913394  -1.441 0.149782    
dist6              0.0477956  0.0995679   0.480 0.631308    
dist7              0.1383000  0.0981247   1.409 0.159011    
dist8             -0.3985620  0.0886316  -4.497 7.69e-06 ***
dist9             -0.2036683  0.0799584  -2.547 0.011005 *  
st11              -0.0258775  0.0591631  -0.437 0.661919    
st21               0.0089230  0.0573352   0.156 0.876356    
di11              -0.0910207  0.0838321  -1.086 0.277846    
min:cot            0.0066210  0.0006195  10.688  < 2e-16 ***
s1:cot            -0.1505670  0.0443186  -3.397 0.000694 ***
s1:min             0.0079478  0.0015051   5.280 1.29e-07 ***
s1:ge2             0.0329272  0.1007943   0.327 0.743948    
s1:ge3             0.2150927  0.1241590   1.732 0.083367 .  
s1:ge4             0.1786057  0.1404119   1.272 0.203526    
s1:ge5            -0.0422380  0.1631757  -0.259 0.795780    
s1:ge6             0.1372051  0.1404415   0.977 0.328717    
s1:ge7             0.1343314  0.1287059   1.044 0.296755    
s1:vis2            0.1354091  0.0765084   1.770 0.076913 .  
s1:vis3            0.2449180  0.1568745   1.561 0.118637    
s1:dur2           -0.0888179  0.0989573  -0.898 0.369547    
s1:dur3           -0.0532473  0.1018481  -0.523 0.601167    
s1:dur4           -0.1239068  0.1112907  -1.113 0.265696    
s1:dur5           -0.1191069  0.1341435  -0.888 0.374705    
s1:mo2            -0.1357615  0.1574365  -0.862 0.388618    
s1:mo3             0.0130976  0.1588743   0.082 0.934306    
s1:mo4             0.0343900  0.1579532   0.218 0.827669    
s1:mo5             0.2257241  0.1732449   1.303 0.192761    
s1:mo6             0.0500347  0.1628755   0.307 0.758728    
s1:mo7            -0.0451271  0.1596277  -0.283 0.777435    
s1:mo8            -0.0200467  0.1572383  -0.127 0.898564    
s1:mo9             0.0394005  0.1584268   0.249 0.803620    
s1:mo10            0.0641038  0.1562518   0.410 0.681662    
s1:mo11           -0.3136235  0.1703456  -1.841 0.065764 .  
s1:mo12           -0.7003775  0.1660455  -4.218 2.58e-05 ***
s1:nps            -0.0095428  0.0013077  -7.297 4.31e-13 ***
s1:dist2          -0.3867962  0.1407463  -2.748 0.006050 ** 
s1:dist3          -0.0516400  0.1140519  -0.453 0.650762    
s1:dist4          -0.0567491  0.2008542  -0.283 0.777562    
s1:dist5           0.0025780  0.1147143   0.022 0.982073    
s1:dist6          -0.1456445  0.1252219  -1.163 0.244940    
s1:dist7          -0.0452712  0.1234110  -0.367 0.713785    
s1:dist8           0.0546400  0.1114865   0.490 0.624117    
s1:dist9           0.0540697  0.1000415   0.540 0.588934    
s1:st11            0.0784027  0.0744677   1.053 0.292549    
s1:st21           -0.0394419  0.0721720  -0.546 0.584788    
s1:di11            0.0463040  0.1055326   0.439 0.660882    
s1:min:cot        -0.0012850  0.0006004  -2.140 0.032344 *  
---
Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1

but with anova() I get :

type3.bonmodele <- lmerTest::anova(test.reml, ddf="Satterthwaite")
Analysis of Variance Table
                  Df  Sum Sq Mean Sq   F value
s1                 1   7.385   7.385   41.1448
min                1   0.081   0.081    0.4536
cot                1  29.384  29.384  163.7026
ge                 6  25.198   4.200   23.3968
vis                2   0.464   0.232    1.2929
dur                4  22.763   5.691   31.7042
mo                11  15.581   1.416    7.8914
nps                1 234.535 234.535 1306.6487
dist               8  18.547   2.318   12.9162
st1                1   0.034   0.034    0.1879
st2                1   0.058   0.058    0.3220
di1                1   0.261   0.261    1.4549
min:cot            1  22.537  22.537  125.5611
s1:cot             1   9.146   9.146   50.9555
s1:min             1  18.383  18.383  102.4171
s1:ge              6   5.152   0.859    4.7843
s1:vis             2   1.698   0.849    4.7311
s1:dur             4   2.829   0.707    3.9404
s1:mo             11   8.157   0.742    4.1312
s1:nps             1  10.102  10.102   56.2803
s1:dist            8   2.233   0.279    1.5550
s1:st1             1   0.188   0.188    1.0481
s1:st2             1   0.046   0.046    0.2560
s1:di1             1   0.035   0.035    0.1927
s1:min:cot         1   0.822   0.822    4.5804

When I try to remove the triple interaction the anova() function returns the p-values...I have also tried to split my data frame and to fit the model on half the data and anova() works well to.

There is no warning when I use the functions and I have also tried to change the ddf option and the method but nothing seems to work.

Here is my session info :

    R version 3.0.0 (2013-04-03)
Platform: x86_64-w64-mingw32/x64 (64-bit)

locale:
[1] LC_COLLATE=French_Canada.1252  LC_CTYPE=French_Canada.1252    LC_MONETARY=French_Canada.1252 LC_NUMERIC=C                  
[5] LC_TIME=French_Canada.1252    

attached base packages:
[1] parallel  splines   stats     graphics  grDevices utils     datasets  methods   base     

other attached packages:
 [1] ggplot2_0.9.3.1 snow_0.3-13     Snowball_0.0-10 xtable_1.7-1    lmerTest_2.0-0  pbkrtest_0.3-7  MASS_7.3-29    
 [8] papeR_0.3       gmodels_2.15.4  survival_2.37-4 nlme_3.1-111    car_2.0-19      lme4_1.1-1      Matrix_1.1-0   
[15] lattice_0.20-15

loaded via a namespace (and not attached):
 [1] bitops_1.0-6       caTools_1.16       cluster_1.14.4     colorspace_1.2-4   dichromat_2.0-0    digest_0.6.3      
 [7] gdata_2.13.2       gplots_2.12.1      grid_3.0.0         gtable_0.1.2       gtools_3.0.0       Hmisc_3.12-2      
[13] KernSmooth_2.23-10 labeling_0.2       minqa_1.2.1        munsell_0.4.2      nnet_7.3-7         numDeriv_2012.9-1 
[19] plyr_1.8           proto_0.3-10       RColorBrewer_1.0-5 RCurl_1.95-4.1     reshape2_1.2.2     rJava_0.9-4       
[25] ROAuth_0.9.3       rpart_4.1-3        scales_0.2.3       stringr_0.6.2      tools_3.0.0        twitteR_1.1.7 

I can't share the data but I can add more infos if needed! I wanted to use the Satterthwaite approximation for the degrees of freedom but if you have any other suggestions to get p-values please share! Thank you very much!

Trahern answered 26/11, 2013 at 5:30 Comment(0)
P
4

If some error occurs in lmerTest then by default the anova from lme4 will be given. So in your case some error occurred, but it is quite hard to say what without testing on the data. Probably it is due to the simple method for the grad function, which is the default. You may try: anova(test.reml, method.grad="Richardson"). Otherwise again like I said quite hard to say without looking at the example...

Alexandra Kuznetsova

Purvis answered 26/11, 2013 at 20:14 Comment(1)
Thank you Alexandra. I've tried to change method.grad to Richardson but I get the same results. Like I said in my previous post it is weird that when I remove the fixed effect for s1:min:cot I could have the Satterthwaite approximations for the ddf and the p-values. I made a test with 0.1% less observations and it worked...Trahern

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