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Analysis of variance for a three-factor factorial experiment in a randomized complete block design (when replication is given) or a completely randomized design, with SEm, SEd and CD for every main effect and interaction and letter groupings for main-effect means and treatment combinations.

Usage

anova_factorial_3way(
  data,
  response,
  factor1,
  factor2,
  factor3,
  replication = NULL,
  alpha = 0.05,
  verbose = TRUE,
  posthoc = "lsd"
)

Arguments

data

Data frame containing the data.

response

Name of the response variable.

factor1

Name of the first factor (A).

factor2

Name of the second factor (B).

factor3

Name of the third factor (C).

replication

Name of the replication (block) column, or NULL for a completely randomized layout.

alpha

Significance level for CD and letters. Default 0.05.

verbose

Logical. If TRUE (default), prints the report.

posthoc

Post-hoc method for the letters (see perform_posthoc). Default "lsd".

Value

An object of class aridagri_factorial3 with anova_table, model, grand_mean, cv, ms_error, df_error, comparisons (SEm, SEd and CD for all seven effects), means (a list of tables for A, B, C, A x B, A x C, B x C and A x B x C, with letters) and posthoc.

Author

Lalit Kumar Rolaniya, Ram Lal Jat, Monika Punia, Raja Ram Choudhary, Hemant Poonia

Examples

data <- expand.grid(rep = 1:3, A = c("A1", "A2"), B = c("B1", "B2"),
                    C = c("C1", "C2", "C3"))
set.seed(2)
data$yield <- rnorm(nrow(data), 1200, 60)
res <- anova_factorial_3way(data, "yield", "A", "B", "C", "rep")
#> 
#> ======================================================================
#>  THREE-FACTOR FACTORIAL (RCBD)
#> ======================================================================
#>  Response     : yield
#>  Factor A     : A
#>  Factor B     : B
#>  Factor C     : C
#>  Observations : 36
#> 
#>  Analysis of variance
#>  Source Df    Sum Sq  Mean Sq F value Pr(>F)   
#>   rep    2  42406.20 21203.10   6.852 0.0049 **
#>   A      1   5505.52  5505.52   1.779 0.1959 NS
#>   B      1  16395.94 16395.94   5.298 0.0312  *
#>   C      2   5626.54  2813.27   0.909 0.4175 NS
#>   A:B    1   2429.03  2429.03   0.785 0.3852 NS
#>   A:C    2    588.81   294.41   0.095 0.9096 NS
#>   B:C    2   3753.96  1876.98   0.607 0.5541 NS
#>   A:B:C  2   9538.89  4769.45   1.541 0.2364 NS
#>   Error 22  68081.18  3094.60                  
#>   Total 35 154326.07                           
#>  Signif. codes: *** p < 0.001, ** p < 0.01, * p < 0.05, NS not significant
#> 
#>  Grand mean = 1212.230   CV = 4.59%
#> 
#>  SE and CD (alpha = 0.05)
#>     Effect Obs_per_mean    SEm    SEd     CD
#>          A           18 13.112 18.543 38.456
#>          B           18 13.112 18.543 38.456
#>          C           12 16.059 22.710 47.099
#>      A x B            9 18.543 26.224 54.385
#>      A x C            6 22.710 32.117 66.608
#>      B x C            6 22.710 32.117 66.608
#>  A x B x C            3 32.117 45.421 94.197
#> 
#>  Means of A
#>   A    Mean     SE Obs Group
#>  A1 1224.60 13.112  18     a
#>  A2 1199.86 13.112  18     a
#> 
#>  Means of B
#>   B    Mean     SE Obs Group
#>  B1 1190.89 13.112  18     b
#>  B2 1233.57 13.112  18     a
#> 
#>  Means of C
#>   C    Mean     SE Obs Group
#>  C1 1217.55 16.059  12     a
#>  C2 1224.17 16.059  12     a
#>  C3 1194.97 16.059  12     a
#> 
#>  Two- and three-way tables are in $means.
res$comparisons
#>      Effect Obs_per_mean      SEm      SEd       CD
#> 1         A           18 13.11191 18.54304 38.45591
#> 2         B           18 13.11191 18.54304 38.45591
#> 3         C           12 16.05874 22.71049 47.09868
#> 4     A x B            9 18.54304 26.22382 54.38487
#> 5     A x C            6 22.71049 32.11749 66.60759
#> 6     B x C            6 22.71049 32.11749 66.60759
#> 7 A x B x C            3 32.11749 45.42099 94.19736