[R-sig-ME] (stupid) results interpretation question

[CL Pressland]

I have a seemingly stupid but fundamental question I need answering.

I've had some strange plots and am now seriously questioning my 
interpretation of the lmer output: if I have a fixed effects results table 
that looks like this, can someone please check I'm interpreting it 
correctly?

---------
Fixed effects:
            Estimate Std. Error t value
1	(Intercept) -1.58481    0.18585   -8.53
2	GM1          0.02400    0.20472    0.12
3	GM2          0.17941    0.15916    1.13
4	Morph1      -1.54068    0.02202  -69.97
5	GM1:Morph1  -0.21681    0.04701   -4.61
6	GM2:Morph1  -0.12910    0.03321   -3.89
---------

1. Intercept is GM0 and Morph0
In my understanding the estimates given are the differences from the 
intercept alone so would give mean values for each category of:
1	-1.58481
2	-1.5601
3	-1.4054
4	-3.12549
5	-1.80162
6	-1.71391

Is this correct? Have I made a mistake in just looking at the difference 
from the intercept or do 2,3 and 4 need to be taken into account when 
calculating 5 and 6 i.e. 6 = 1 + 3 + 4?

I don't want to plough through thinking I've understood this when I may not 
have! I've tried looking in Pinheiro and Bates etc but they all just say 
the "estimate is the difference in the means" - I want to make sure I'm 
interpreting it correctly.

Anyone who can spare this simpleton student a swift reply would really help 
me out.

----------------------
Kate Pressland
School of Biological Sciences
University of Bristol
Woodland Road
Bristol, BS8 1UG

Kate.Pressland at bristol.ac.uk