I wantto run sequential ANOVAs (i.e. type I sums of squares), and trying to
getresults including ANOVA tables and associated coefficients for predictive
variables(I am using the R 3.4.2 version). I think ANOVA tables look right, but
believecoefficients are wrong. Specifically, it looks like that the
coefficients arefrom ANOVA with “marginal” (type III sums of squares). I have
tried both lme (nlmepackage) and lmer (lme4 + lmerTEST packages). Examples of
the results arebelow:
> #mixed-effect modelusing lme
>model.short.psme.bulk.d13c.3 <- lme(isotopebulk_add_log ~narea+sampleheight,
>random= ~1|tree,
+ data =ht_data_short_psme, na.action = na.exclude)
>
>anova(model.short.psme.bulk.d13c.3, type ="sequential")
numDF denDF F-value p-value
(Intercept) 1 3 1840.5678 <.0001
narea 1 2 18.4876 0.0501
sampleheight 1 2 11.6159 0.0764
>anova(model.short.psme.bulk.d13c.3, type ="marginal")
numDF denDF F-value p-value
(Intercept) 1 3 629.4711 0.0001
narea 1 2 2.7831 0.2372
sampleheight 1 2 11.6159 0.0764
>
>summary(model.short.psme.bulk.d13c.3, type ="sequential")$tTable
Value Std.Error DF t-value p-value
(Intercept) 1.76871397 0.07049685 3 25.089262 0.0001388446
narea -0.09295561 0.05571991 2 -1.668266 0.2372012082
sampleheight 0.13232709 0.03882599 2 3.408209 0.0763589527
(Intercept) 1.76871397 0.07049685 3 25.0892620.0001388446
>summary(model.short.psme.bulk.d13c.3, type ="marginal")$tTable
Value Std.Error DF t-value p-value
(Intercept) 1.76871397 0.07049685 3 25.089262 0.0001388446
narea -0.09295561 0.05571991 2 -1.668266 0.2372012082
sampleheight 0.13232709 0.03882599 2 3.408209 0.0763589527
Ibelieve the results from summary() are for “marginal” instead of
“sequential”ANOVA because the p-value (i.e., 0.237 for narea) in summary are
identical tothose in tables from “marginal”. I also used lmer in the lme4
pacakge to findthe same results (summary() results look like from “marginal”).
Cananybody tell me how to get coefficients for “sequential” ANOVAs? Thank you.
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