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Exam4.3.1 presents the germination count data for 4 Pre-Treatments and 6 Seedlots.

References

  1. E.R. Williams, C.E. Harwood and A.C. Matheson (2023). Experimental Design and Analysis for Tree Improvement. CSIRO Publishing (https://www.publish.csiro.au/book/3145/).

See also

Author

  1. Muhammad Yaseen (myaseen208@gmail.com)

  2. Sami Ullah (samiullahuos@gmail.com)

Examples

library(car)
library(dae)
library(dplyr)
library(emmeans)
library(ggplot2)
library(lmerTest)
library(magrittr)
library(predictmeans)

data(DataExam4.3)

# Pg. 57
fm4.4    <-
  aov(
      formula = percent ~ repl + treat*seedlot
    , data    = DataExam4.3 %>%
                 filter(treat != "control")
     )

 # Pg. 57
 anova(fm4.4)
#> Analysis of Variance Table
#> 
#> Response: percent
#>               Df Sum Sq Mean Sq F value    Pr(>F)    
#> repl           2   64.6   32.30  0.2511 0.7793606    
#> treat          2 5300.1 2650.07 20.6055 1.375e-06 ***
#> seedlot        5 4148.1  829.63  6.4507 0.0002578 ***
#> treat:seedlot 10  961.2   96.12  0.7474 0.6759614    
#> Residuals     34 4372.7  128.61                      
#> ---
#> Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1
 model.tables(x = fm4.4, type = "means", se = TRUE)
#> Tables of means
#> Grand mean
#>          
#> 67.85185 
#> 
#>  repl 
#> repl
#>     1     2     3 
#> 69.11 66.44 68.00 
#> 
#>  treat 
#> treat
#>   nick   bw&s bw1min 
#>  56.89  65.78  80.89 
#> 
#>  seedlot 
#> seedlot
#> 18211 18212 18217 18248 18249 18265 
#> 77.33 69.33 63.11 53.33 64.89 79.11 
#> 
#>  treat:seedlot 
#>         seedlot
#> treat    18211 18212 18217 18248 18249 18265
#>   nick   65.33 54.67 57.33 40.00 49.33 74.67
#>   bw&s   78.67 68.00 54.67 52.00 61.33 80.00
#>   bw1min 88.00 85.33 77.33 68.00 84.00 82.67
#> 
#> Standard errors for differences of means
#>          repl treat seedlot treat:seedlot
#>         3.780 3.780   5.346         9.260
#> replic.    18    18       9             3

 emmeans(object = fm4.4, specs = ~ treat)
#> NOTE: Results may be misleading due to involvement in interactions
#>  treat  emmean   SE df lower.CL upper.CL
#>  nick     56.9 2.67 34     51.5     62.3
#>  bw&s     65.8 2.67 34     60.3     71.2
#>  bw1min   80.9 2.67 34     75.5     86.3
#> 
#> Results are averaged over the levels of: repl, seedlot 
#> Confidence level used: 0.95 
 emmeans(object = fm4.4, specs = ~ seedlot)
#> NOTE: Results may be misleading due to involvement in interactions
#>  seedlot emmean   SE df lower.CL upper.CL
#>  18211     77.3 3.78 34     69.7     85.0
#>  18212     69.3 3.78 34     61.7     77.0
#>  18217     63.1 3.78 34     55.4     70.8
#>  18248     53.3 3.78 34     45.7     61.0
#>  18249     64.9 3.78 34     57.2     72.6
#>  18265     79.1 3.78 34     71.4     86.8
#> 
#> Results are averaged over the levels of: repl, treat 
#> Confidence level used: 0.95 
 emmeans(object = fm4.4, specs = ~ treat * seedlot)
#>  treat  seedlot emmean   SE df lower.CL upper.CL
#>  nick   18211     65.3 6.55 34     52.0     78.6
#>  bw&s   18211     78.7 6.55 34     65.4     92.0
#>  bw1min 18211     88.0 6.55 34     74.7    101.3
#>  nick   18212     54.7 6.55 34     41.4     68.0
#>  bw&s   18212     68.0 6.55 34     54.7     81.3
#>  bw1min 18212     85.3 6.55 34     72.0     98.6
#>  nick   18217     57.3 6.55 34     44.0     70.6
#>  bw&s   18217     54.7 6.55 34     41.4     68.0
#>  bw1min 18217     77.3 6.55 34     64.0     90.6
#>  nick   18248     40.0 6.55 34     26.7     53.3
#>  bw&s   18248     52.0 6.55 34     38.7     65.3
#>  bw1min 18248     68.0 6.55 34     54.7     81.3
#>  nick   18249     49.3 6.55 34     36.0     62.6
#>  bw&s   18249     61.3 6.55 34     48.0     74.6
#>  bw1min 18249     84.0 6.55 34     70.7     97.3
#>  nick   18265     74.7 6.55 34     61.4     88.0
#>  bw&s   18265     80.0 6.55 34     66.7     93.3
#>  bw1min 18265     82.7 6.55 34     69.4     96.0
#> 
#> Results are averaged over the levels of: repl 
#> Confidence level used: 0.95