On 10 May 2008, at 07:36, Kingsford Jones wrote:
Federico,

I think you'll be more likely to receive the type of response you're
looking for if you formulate your question more clearly.  The
inclusion of "commented, minimal, self-contained, reproducible code"
(as is requested at the bottom of every email sent by r-help) is an
effective way to clarify the issues.  Also, when asking a question
about fitting a model it's helpful to describe the specific research
questions you want the model to answer.

<snip>

I apprecciate that my description of the *full* model is not 100% clear, but my main beef was another.

The main point of my question is, having a 3 way anova (or ancova, if you prefer), with *no* nesting, 2 fixed effects and 1 random effect, why is it so boneheaded difficult to specify a bog standard fully crossed model? I'm not talking about some rarified esoteric model here, we're talking about stuff tought in a first year Biology Stats course here[1].

Now, to avoid any chances of being misunderstood in my use of the words 'fully crossed model', what I mean is a simple

y ~ effect1 * effect2 * effect3

with effect3 being random (all all the jazz that comes from this fact). I fully apprecciate that the only reasonable F-tests would be for effect1, effect2 and effect1:effect2, but there is no way I can use lme to specify such simple thing without getting the *wrong* denDF. I need light on this topic and I'd say it's a general enough question not to need much more handholding than this.

Having said that, I did look at the mixed-effects mailing list before posting here, and it looks like it was *not* the right place to post anyway:

'This mailing list is primarily for useRs and programmeRs interested in *development* and beta-testing of the lme4 package.'

although the R-Me is now CC'd in this.

I fully apprecciate that R is developed for love, not money, and if I knew how to write an user friendly frontend for nlme and lme4 (and I knew how to actually get the model I want) I'd be pretty happy to do so and submit it as a library. In any case, I feel my complaint is pefectly valid, because specifying such basic model should ideally not such a chore, and I think the powers that be might actually find some use from user feedback.

Once I have sorted how to specify such trivial model I'll face the horror of the nesting, in any case I attach a toy dataset I created especially to test how to specify the correct model (silly me).

Best,

Federico Calboli

[1] So much bog standard that the Zar, IV ed, gives a nice table of how to compute the F-tests correctly, taking into account that one of the 3 effects is randon (I'll send the exact page and table number tomorrow, I don't have the book at home).

selection       line    males   month   block   y
L       L1      1       a       1       13.8156357121188
L       L1      1       a       1       12.5678496952169
L       L1      1       a       1       17.1313698710874
L       L1      1       a       1       3.87016302696429
L       L1      1       a       1       13.2627072110772
L       L2      1       a       1       17.835768135963
L       L2      1       a       1       19.3615794742946
L       L2      1       a       1       1.73416316602379
L       L2      1       a       1       12.9440758333076
L       L2      1       a       1       2.09191741654649
S       S1      1       a       1       1.56137526640669
S       S1      1       a       1       17.6580698778853
S       S1      1       a       1       18.1417595115490
S       S1      1       a       1       15.5621050691698
S       S1      1       a       1       17.0240987658035
S       S2      1       a       1       12.4378062419128
S       S2      1       a       1       6.63962595071644
S       S2      1       a       1       16.6060689473525
S       S2      1       a       1       7.1222553497646
S       S2      1       a       1       18.0590278783347
L       L1      2       a       1       1.24710303940810
L       L1      2       a       1       4.62720696791075
L       L1      2       a       1       16.0327167815994
L       L1      2       a       1       6.12926463945769
L       L1      2       a       1       7.65810538828373
L       L2      2       a       1       7.44077128893696
L       L2      2       a       1       14.9197938004509
L       L2      2       a       1       13.4244954204187
L       L2      2       a       1       11.5361888066400
L       L2      2       a       1       2.60056478204206
S       S1      2       a       1       14.8965472229756
S       S1      2       a       1       18.777876078384
S       S1      2       a       1       6.80722737265751
S       S1      2       a       1       13.1697203880176
S       S1      2       a       1       3.74557441123761
S       S2      2       a       1       5.41025308240205
S       S2      2       a       1       19.8277674221899
S       S2      2       a       1       4.76206006342545
S       S2      2       a       1       3.08200096315704
S       S2      2       a       1       11.7220768791158
L       L1      1       a       2       17.8684629611671
L       L1      1       a       2       18.5609889889602
L       L1      1       a       2       1.33335256157443
L       L1      1       a       2       12.2590920312796
L       L1      1       a       2       10.3133576815017
L       L2      1       a       2       9.08117202203721
L       L2      1       a       2       11.8387454338372
L       L2      1       a       2       2.17258459446020
L       L2      1       a       2       7.64467771397904
L       L2      1       a       2       10.1472946784925
S       S1      1       a       2       6.33078282815404
S       S1      1       a       2       14.2109518861398
S       S1      1       a       2       2.86901426501572
S       S1      1       a       2       1.33705932833254
S       S1      1       a       2       3.62769498769194
S       S2      1       a       2       10.6116549053695
S       S2      1       a       2       19.2579759012442
S       S2      1       a       2       4.93543729488738
S       S2      1       a       2       14.0185110287275
S       S2      1       a       2       13.0477287801914
L       L1      2       a       2       7.81632485729642
L       L1      2       a       2       15.8365131700411
L       L1      2       a       2       13.6505087725818
L       L1      2       a       2       4.30545190884732
L       L1      2       a       2       5.62008981755935
L       L2      2       a       2       11.6415019945707
L       L2      2       a       2       17.4424436504487
L       L2      2       a       2       5.51907726703212
L       L2      2       a       2       3.24006642703898
L       L2      2       a       2       2.96195078082383
S       S1      2       a       2       16.2962908495683
S       S1      2       a       2       11.919979267288
S       S1      2       a       2       2.93063819734380
S       S1      2       a       2       15.6936508698855
S       S1      2       a       2       2.295168728102
S       S2      2       a       2       11.7390888168011
S       S2      2       a       2       10.4391786744818
S       S2      2       a       2       11.1727120177820
S       S2      2       a       2       11.4406719871331
S       S2      2       a       2       5.20650001661852
L       L1      1       b       3       9.53833453846164
L       L1      1       b       3       1.95979442284442
L       L1      1       b       3       8.31046994985081
L       L1      1       b       3       4.39192276610993
L       L1      1       b       3       16.0887561799027
L       L2      1       b       3       5.20481191016734
L       L2      1       b       3       8.32888073613867
L       L2      1       b       3       3.47083900799043
L       L2      1       b       3       12.2260039008688
L       L2      1       b       3       12.2011876017787
S       S1      1       b       3       10.6229240614921
S       S1      1       b       3       9.49411644623615
S       S1      1       b       3       18.4179708964657
S       S1      1       b       3       4.12228938611224
S       S1      1       b       3       5.55325478035957
S       S2      1       b       3       10.4130052563269
S       S2      1       b       3       12.6257456133608
S       S2      1       b       3       19.8305484240409
S       S2      1       b       3       2.6487210446503
S       S2      1       b       3       15.9869729799684
L       L1      2       b       3       14.6902481422294
L       L1      2       b       3       16.9090498948935
L       L1      2       b       3       3.90413530776277
L       L1      2       b       3       1.89122105599381
L       L1      2       b       3       14.2131580882706
L       L2      2       b       3       16.1121652075090
L       L2      2       b       3       16.8070402105805
L       L2      2       b       3       2.19568496150896
L       L2      2       b       3       2.96183063089848
L       L2      2       b       3       12.6824307644274
S       S1      2       b       3       12.8504637307487
S       S1      2       b       3       6.1809710978996
S       S1      2       b       3       7.47571811126545
S       S1      2       b       3       8.81466605700552
S       S1      2       b       3       12.3395618333016
S       S2      2       b       3       19.9728567516431
S       S2      2       b       3       11.3028548071161
S       S2      2       b       3       6.50141697842628
S       S2      2       b       3       13.0698232366703
S       S2      2       b       3       11.474319845438
L       L1      1       b       4       1.03187379334122
L       L1      1       b       4       9.6801089819055
L       L1      1       b       4       4.00592510355636
L       L1      1       b       4       4.63362230593339
L       L1      1       b       4       15.4505966042634
L       L2      1       b       4       14.9346919001546
L       L2      1       b       4       18.3153922208585
L       L2      1       b       4       8.57050257665105
L       L2      1       b       4       1.31918784533627
L       L2      1       b       4       19.5731912786141
S       S1      1       b       4       4.34415089036338
S       S1      1       b       4       9.66746214497834
S       S1      1       b       4       12.4202494181227
S       S1      1       b       4       17.0269973296672
S       S1      1       b       4       15.1591323411558
S       S2      1       b       4       7.3169305799529
S       S2      1       b       4       14.9331590640359
S       S2      1       b       4       13.4191052850801
S       S2      1       b       4       3.8695620871149
S       S2      1       b       4       14.8654785933904
L       L1      2       b       4       18.5652933202218
L       L1      2       b       4       1.33474090369418
L       L1      2       b       4       12.9836367180105
L       L1      2       b       4       8.14379613753408
L       L1      2       b       4       17.5245339989197
L       L2      2       b       4       19.4962712256238
L       L2      2       b       4       8.36269160197116
L       L2      2       b       4       16.4331527492031
L       L2      2       b       4       19.9028004400898
L       L2      2       b       4       8.9440936667379
S       S1      2       b       4       5.1467830883339
S       S1      2       b       4       13.0068403361365
S       S1      2       b       4       17.9727395507507
S       S1      2       b       4       7.75389035535045
S       S1      2       b       4       13.1991689843126
S       S2      2       b       4       1.86596546205692
S       S2      2       b       4       13.6726454407908
S       S2      2       b       4       5.46787238144316
S       S2      2       b       4       14.9116268747021
S       S2      2       b       4       17.4470446316991
L       L1      1       c       5       6.0449733575806
L       L1      1       c       5       9.23758197389543
L       L1      1       c       5       11.8805425714236
L       L1      1       c       5       11.097381018335
L       L1      1       c       5       6.2186355558224
L       L2      1       c       5       15.4524628254585
L       L2      1       c       5       10.8791305767372
L       L2      1       c       5       8.53259862400591
L       L2      1       c       5       17.7329147965647
L       L2      1       c       5       7.95771266217344
S       S1      1       c       5       14.2891584723257
S       S1      1       c       5       18.7194010075182
S       S1      1       c       5       5.8396331758704
S       S1      1       c       5       12.2250114120543
S       S1      1       c       5       19.9965940725524
S       S2      1       c       5       8.086333316518
S       S2      1       c       5       1.02154314704239
S       S2      1       c       5       2.71978635899723
S       S2      1       c       5       11.7734509080183
S       S2      1       c       5       10.7842262475751
L       L1      2       c       5       15.3013315075077
L       L1      2       c       5       6.12277858285233
L       L1      2       c       5       6.58965252665803
L       L1      2       c       5       13.0980647155084
L       L1      2       c       5       11.3858233471401
L       L2      2       c       5       13.8056075817440
L       L2      2       c       5       11.4665438272059
L       L2      2       c       5       6.37498314119875
L       L2      2       c       5       3.85318743507378
L       L2      2       c       5       7.959969348507
S       S1      2       c       5       13.8249646106269
S       S1      2       c       5       13.3112728327978
S       S1      2       c       5       9.67586784437299
S       S1      2       c       5       17.8595201659482
S       S1      2       c       5       3.14554875413887
S       S2      2       c       5       10.4300375301391
S       S2      2       c       5       15.4386686717626
S       S2      2       c       5       7.93477151589468
S       S2      2       c       5       3.66100515658036
S       S2      2       c       5       13.5765222932678
L       L1      1       c       6       11.3484169594012
L       L1      1       c       6       12.7286028855015
L       L1      1       c       6       17.2616694702301
L       L1      1       c       6       19.8529832861386
L       L1      1       c       6       13.6375724875834
L       L2      1       c       6       1.47241126280278
L       L2      1       c       6       1.95706973574124
L       L2      1       c       6       5.88739864598028
L       L2      1       c       6       8.16921139019541
L       L2      1       c       6       15.4799758975860
S       S1      1       c       6       2.47244948730804
S       S1      1       c       6       4.87303283042274
S       S1      1       c       6       6.15663269115612
S       S1      1       c       6       1.31718108500354
S       S1      1       c       6       16.4325702653732
S       S2      1       c       6       8.77171974466182
S       S2      1       c       6       13.4219867731445
S       S2      1       c       6       15.79551491444
S       S2      1       c       6       8.52955200499855
S       S2      1       c       6       14.4046092615463
L       L1      2       c       6       17.4255252447911
L       L1      2       c       6       5.80786765902303
L       L1      2       c       6       3.27889802469872
L       L1      2       c       6       7.55257236934267
L       L1      2       c       6       10.3537469459698
L       L2      2       c       6       10.1472219382413
L       L2      2       c       6       15.3184245729353
L       L2      2       c       6       12.6165662519634
L       L2      2       c       6       11.2075877587777
L       L2      2       c       6       17.0927850408480
S       S1      2       c       6       19.5778706537094
S       S1      2       c       6       5.56091665173881
S       S1      2       c       6       6.32830694783479
S       S1      2       c       6       7.46368952002376
S       S1      2       c       6       14.5648785342928
S       S2      2       c       6       14.7789344959892
S       S2      2       c       6       3.21725518512540
S       S2      2       c       6       2.26359746395610
S       S2      2       c       6       9.14707987429574
S       S2      2       c       6       8.6291270784568

--
Federico C. F. Calboli
Department of Epidemiology and Public Health
Imperial College, St. Mary's Campus
Norfolk Place, London W2 1PG

Tel +44 (0)20 75941602   Fax +44 (0)20 75943193

f.calboli [.a.t] imperial.ac.uk
f.calboli [.a.t] gmail.com



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