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AUKEEP procedure

Saves output from analysis of an unbalanced design (by AUNBALANCED) (R.W. Payne).

Options

FACTORIAL = scalar Limit on number of factors in the model terms generated from the TERMS parameter; default 3
RESIDUALS = variate To save residuals from the analysis
FITTEDVALUES = variate To save fitted values
COMBINATIONS = string token Factor combinations for which to form predicted means (present, estimable); default esti
ADJUSTMENT = string token Type of adjustment to be made when predicting means (marginal, equal, observed); default marg
LSDLEVEL = scalar Significance level (as a percentage) for the least significant differences
RMETHOD = string token Type of residuals to form if the RESIDUALS option is set (simple, standardized); default simp
SAVE = identifier Save structure (from AUNBALANCED) containing details of the analysis for which further output is required; if omitted, output is from the most recent use of AUNBALANCED

Parameters

TERMS = formula Model terms for which information is required
MEANS = table or pointer to tables Predicted means for each term
SEMEANS = table or pointer to tables Standard errors of the means for each term
SEDMEANS = symmetric matrix or pointer to symmetric matrices Standard errors of differences between means
ESEMEANS = table or pointer to tables Approximate effective standard errors of the means: these are formed by procedure SED2ESE with the aim of allowing good approximations to the standard errors for differences to be calculated by the usual formula sedi,j = √( esei2 + esej2 )
LSD = symmetric matrix or pointer to symmetric matrices Least significant differences

Description

This procedure can be used, following the use of procedure AUNBALANCED, to save output for the analysis of variance of an unbalanced design.

Options are provided to save information about the analysis as a whole. The RESIDUALS and FITTEDVALUES options allow variates to be specified to store the residuals and fitted values, respectively. The RMETHOD option controls whether simple or standardized residuals are saved; by default RMETHOD=simple.

The SAVE option can be set to the save structure from the analysis from which output is to be saved. If SAVE is not set, output will be produced for the most recent analysis from AUNBALANCED; however, none of the Genstat regression directives (MODEL, TERMS, FIT, ADD, DROP and so on) must then have been used in the interim.

The parameters of AUKEEP save information about particular model terms in the analysis. With the TERMS parameter you specify a model formula, which Genstat expands to form the series of model terms about which you wish to save information. As in AUNBALANCED, the FACTORIAL option sets a limit on the number of factors in each term. Any term containing more than that limit is deleted. The subsequent parameters allow you to specify identifiers of data structures to store various components of information for each of the terms that you have specified. The MEANS parameter saves tables of predicted means, the SEMEANS parameter saves tables of standard errors for the means, the SEDMEANS parameter saves symmetric matrices of standard errors of differences, the ESEMEANS parameter saves tables of approximate effective standard errors, and the LSD parameter saves symmetric matrices of least significant differences. If you have a single term, you can supply a table or symmetric matrix for each of these parameters, as appropriate. However, if you have several terms, you must supply a pointer which will then be set up to contain as many tables or symmetric matrices as there are terms. The LSDLEVEL option sets the significance level (as a percentage) for the least significant differences.

Tables of means are calculated using the PREDICT directive. The first step (A) of the calculation forms the full table of predictions, classified by every factor in the model. The second step (B) averages the full table over the factors that do not occur in the table of means. The COMBINATIONS option specifies which cells of the full table are to be formed in Step A. The default setting, estimable, fills in all the cells other than those that involve parameters that cannot be estimated, for example because of aliasing. Alternatively, setting COMBINATIONS=present excludes the cells for factor combinations that do not occur in the data. The ADJUSTMENT option then defines how the averaging is done in Step B. The default setting, marginal, forms a table of marginal weights for each factor, containing the proportion of observations with each of its levels; the full table of weights is then formed from the product of the marginal tables. The setting equal weights all the combinations equally. Finally, the setting observed uses the WEIGHTS option of PREDICT to weight each factor combination according to its own individual replication in the data.

Options: FACTORIAL, RESIDUALS, FITTEDVALUES, COMBINATIONS, ADJUSTMENT, LSDLEVEL, RMETHOD, SAVE.

Parameters: TERMS, MEANS, SEMEANS, SEDMEANS, ESEMEANS, LSD.

Method

The output is obtained mainly using the directives RKEEP and PREDICT.

Action with RESTRICT

If the y-variate originally analysed by AUNBALANCED was restricted, only the units not excluded by the restriction will have been analysed.

See also

Procedures: AUNBALANCED, AUDISPLAY, AUGRAPH, AUPREDICT, AUMCOMPARISON.

Commands for: Analysis of variance.

Example

CAPTION 'AUKEEP example',\
        'Data from Genstat 5 Release 1 Reference Manual, page 340.';\
        STYLE=meta,plain
FACTOR  [NVALUES=36; LEVELS=3; VALUES=12(1...3)] Block
FACTOR  [NVALUES=36; LABELS=!t(baresoil,emerald,emergo)] Leachate
&       [LABELS=!t('1','1/4','1/16','1/64')] Dilution
VARIATE [NVALUES=36] Nhatch,Nnohatch
READ    Leachate,Dilution,Nhatch,Nnohatch
  1           2         109         318
  3           4          54         350
  3           1           *         415
  2           2         783         212
  3           3         652        1375
  2           4         490         816
  1           3          95        1219
  2           1        1012          66
  1           4         166         943
  3           2        1059         313
  1           1         257        1006
  2           3        1058         234
  2           4         507        1119
  1           2         194         840
  1           3         175        1707
  1           1         326         609
  3           4         142         980
  2           3         286         230
  3           2         546         313
  2           2           *         301
  2           1        2471         112
  3           3          76         489
  1           4         208         503
  3           1           *         325
  1           1         322         913
  1           2         255        2246
  3           2        1774        1446
  2           2         999         193
  2           4         388        1836
  3           4         221        1800
  1           3         220        1902
  2           1        2821         187
  3           1        1486         463
  3           3         717        1473
  1           4         143         941
  2           3         968         550 :
CALCULATE          Logit%h = LOG(Nhatch/Nnohatch)
BLOCKSTRUCTURE     Block
TREATMENTSTRUCTURE Leachate*Dilution
AUNBALANCED        [PRINT=*] Logit%h
AUKEEP             Leachate + Dilution;\
                   MEANS=!p(LeachateMeans,DilutionMeans);\
                   SEDMEANS=!p(LeachateSED,DilutionSED)
PRINT              [RLPRINT=integers,labels,identifiers;\
                   CLPRINT=integers,identifiers]\
                   LeachateMeans,LeachateSED,DilutionMeans,DilutionSED
Updated on June 20, 2019

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