11 Esquema fatoria duplo


11.1 Teoria


Nos experimentos mais simples comparamos níveis (tratamentos) de apenas um fator; Entretanto, existem casos em que dois ou mais fatores devem ser estudados simultaneamente para que possam nos conduzir a resultados de interesse;

Em geral, os experimentos fatoriais são mais eficientes para este tipo de experimento, pois estudam, ao mesmo tempo, os efeitos de dois ou mais fatores, cada um deles com dois ou mais níveis.

O fatorial é um tipo de esquema, ou seja, uma das maneiras de organizar os tratamentos e não um tipo de delineamento;

Os experimentos fatoriais são montados segundo um tipo de delineamento experimental;

Nos experimentos fatoriais, os tratamentos são obtidos pelas combinações dos níveis dos fatores.



11.1.1 Tipos de efeitos avaliados



  • Efeito Principal: é o efeito de cada fator, independente do efeito dos outros fatores;

  • Efeito de Interação: é o efeito simultâneo dos fatores sobre a variável em estudo. Dizemos que ocorre interação entre os fatores quando os efeitos dos níveis de um fator são modificados pelos níveis do outro fator.



11.1.2 Vantagens



  1. Pode-se estudar dois ou mais fatores num único experimento.

  2. Pode-se, por meio dos efeitos das interações, verificar se um fator é independente ou dependente do(s) outro(s).


11.1.3 Desvantagens



  1. O número de tratamentos ou combinações de níveis de fatores cresce, rapidamente, com o aumento do número de níveis, em cada fator, ou mesmo com o aumento do número de fatores.

  2. A interpretação dos resultados se torna mais difícil é medida que aumentamos o número de níveis e de fatores no experimento.



11.1.4 Modelo estatístico



As observações podem ser descritas pelo modelo estatístico linear:

\(y_{ij} = \mu+\tau_{i}+\beta_{j}+(\tau\beta)_{ij}+\epsilon_{ij}\)

  • i = 1; 2; : : : ; a
  • j = 1; 2; : : : ; b
  • k = 1; 2; : : : ; r

em que:

  • \(y_{ijk}\) é o valor observado no i-ésimo nivel do Fator A e j-ésima nível do Fator B;
  • \(\mu\) é uma constante;
  • \(\tau_{i}\) é o efeito do i-ésimo nível do fator A;
  • \(\beta_{j}\) é o efeito do j-ésimo nível do fator B;
  • \((\tau\beta)_ij\) é o efeito da interação entre \(\tau_{i}\) e \(\beta_{j}\);
  • \((\epsilon)ijk\) é o componente de erro aleatório.



11.1.5 Hipóteses e quadro da análise de variância



No experimento fatorial com 2 fatores, deseja-se testar a signicância de ambos os fatores.

Há interesse em testar hipóteses sobre a igualdade dos efeitos do fator A, isto é:

  • H0 : \(\beta_{11}\) = \(\beta_{12}\) = : : : \(\beta_{1a}\) = 0
  • H1 : Pelo menos um \(\beta_{1i} \neq 0\)

e a igualdade nos efeitos do fator B, ou seja:

  • H0 : \(\beta_{21}\) = \(\beta_{22}\) = : : : \(\beta_{2b}\) = 0
  • H1 : Pelo menos um \(\beta_{2j} \neq 0\)

e, ainda, se há interação entre os fatores:

  • H0 : \((\beta_1\beta_2)_{ij}\) = 0 para todo i ; j
  • H1 : Pelo menos um \((\beta_1\beta_2)_{ij} \neq 0\)
CV G.L. S.Q. Q.M. Fcalc
Fator A \(a - 1\) \(SQ_{A}\) \(\frac{SQ_{A}}{a-1}\) \(\frac{QM_{A}}{QM_{Res}}\)
Fator B \(b-1\) \(SQ_{B}\) \(\frac{SQ_{B}}{b-1}\) \(\frac{QM_{B}}{QM_{Res}}\)
Interação A x B \((a-1)(b-1)\) \(SQ_{AxB}\) \(\frac{SQ_{AxB}}{(a-1)(b-1)}\) \(\frac{QM_{AxB}}{QM_{Res}}\)
resíduo \(ab(n-1)\) \(SQ_{Res}\) \(\frac{SQ_{Res(b)}}{ab(n-1)}\)
Total \(abn-1\) \(SQ_{Total}\) -


11.2 FAT2DIC

data(cloro)
with(cloro,
     FAT2DIC(f1, f2, resp, ylab="Number of nodules", legend = "Stages"))
## 
## -----------------------------------------------------------------
## Normality of errors
## -----------------------------------------------------------------
##                          Method Statistic   p.value
##  Shapiro-Wilk normality test(W) 0.9680878 0.3125183
## As the calculated p-value is greater than the 5% significance level, hypothesis H0 is not rejected. Therefore, errors can be considered normal
## 
## -----------------------------------------------------------------
## Homogeneity of Variances
## -----------------------------------------------------------------
##                               Method Statistic   p.value
##  Bartlett test(Bartlett's K-squared)  9.875441 0.1957427
## As the calculated p-value is greater than the 5% significance level, hypothesis H0 is not rejected. Therefore, the variances can be considered homogeneous
## 
## -----------------------------------------------------------------
## Independence from errors
## -----------------------------------------------------------------
##                  Method Statistic   p.value
##  Durbin-Watson test(DW)  2.092504 0.1892105
## As the calculated p-value is greater than the 5% significance level, hypothesis H0 is not rejected. Therefore, errors can be considered independent
## 
## -----------------------------------------------------------------
## Additional Information
## -----------------------------------------------------------------
## 
## CV (%) =  29.83
## Mean =  218.35
## Median =  185
## Possible outliers =  No discrepant point
## 
## -----------------------------------------------------------------
## Analysis of Variance
## -----------------------------------------------------------------
##               Df   Sum Sq  Mean.Sq   F value        Pr(F)
## Fator1         1  16160.4  16160.4  3.810516 5.972867e-02
## Fator2         3 116554.5  38851.5  9.160929 1.596453e-04
## Fator1:Fator2  3 452096.2 150698.7 35.533773 2.663131e-10
## Residuals     32 135712.0   4241.0
## 

## -----------------------------------------------------------------
## Significant interaction: analyzing the interaction
## -----------------------------------------------------------------
## 
## -----------------------------------------------------------------
## Analyzing  F1  inside of each level of  F2
## -----------------------------------------------------------------
## 
##                          Df Sum Sq Mean Sq F value    Pr(>F)    
## Fator2                    3 116555   38852  9.1609 0.0001596 ***
## Fator2:Fator1             4 468257  117064 27.6030 5.661e-10 ***
##   Fator2:Fator1: Plantio  1  26112   26112  6.1571 0.0185315 *  
##   Fator2:Fator1: V1+15    1 258888  258888 61.0441 6.522e-09 ***
##   Fator2:Fator1: V3+15    1 112360  112360 26.4938 1.295e-05 ***
##   Fator2:Fator1: R1+15    1  70896   70896 16.7169 0.0002728 ***
## Residuals                32 135712    4241                      
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## -----------------------------------------------------------------
## Analyzing  F2  inside of the level of  F1
## -----------------------------------------------------------------
## 
##                     Df Sum Sq Mean Sq F value    Pr(>F)    
## Fator1               1  16160   16160  3.8105  0.059729 .  
## Fator1:Fator2        6 568651   94775 22.3474 3.699e-10 ***
##   Fator1:Fator2: IN  3  75470   25157  5.9318  0.002454 ** 
##   Fator1:Fator2: NI  3 493181  164394 38.7629 9.117e-11 ***
## Residuals           32 135712    4241                      
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## -----------------------------------------------------------------
## Final table
## -----------------------------------------------------------------
##     Plantio    V1+15    V3+15     R1+15
## IN 272.8 aA 140.4 bB 304.0 aA 236.6 aAB
## NI 170.6 bB 462.2 aA  92.0 bB   68.2 bB
## 
## 
## Averages followed by the same lowercase letter in the column and 
## uppercase in the row do not differ by the tukey (p< 0.05 )

11.3 FAT2DBC

data(cloro)
with(cloro,
     FAT2DBC(f1, f2, bloco, resp, ylab="Number of nodules", legend = "Stages"))
## 
## -----------------------------------------------------------------
## Normality of errors
## -----------------------------------------------------------------
##                          Method Statistic   p.value
##  Shapiro-Wilk normality test(W) 0.9548911 0.1117923
## As the calculated p-value is greater than the 5% significance level, hypothesis H0 is not rejected. Therefore, errors can be considered normal
## 
## -----------------------------------------------------------------
## Homogeneity of Variances
## -----------------------------------------------------------------
##                               Method Statistic    p.value
##  Bartlett test(Bartlett's K-squared)  16.11086 0.02412261
## As the calculated p-value is less than the 5% significance level, H0 is rejected. Therefore, the variances are not homogeneous
## 
## -----------------------------------------------------------------
## Independence from errors
## -----------------------------------------------------------------
##                  Method Statistic   p.value
##  Durbin-Watson test(DW)  2.047899 0.1769663
## As the calculated p-value is greater than the 5% significance level, hypothesis H0 is not rejected. Therefore, errors can be considered independent
## 
## -----------------------------------------------------------------
## Additional Information
## -----------------------------------------------------------------
## 
## CV (%) =  30.49
## Mean =  218.35
## Median =  185
## Possible outliers =  No discrepant point
## 
## -----------------------------------------------------------------
## Analysis of Variance
## -----------------------------------------------------------------
##               Df   Sum Sq    Mean.Sq    F value        Pr(F)
## Fator1         1  16160.4  16160.400  3.6462291 6.649143e-02
## Fator2         3 116554.5  38851.500  8.7659631 2.933552e-04
## bloco          4  11613.6   2903.400  0.6550866 6.282168e-01
## Fator1:Fator2  3 452096.2 150698.733 34.0017642 1.790168e-09
## Residuals     28 124098.4   4432.086
## 
##  Your analysis is not valid, suggests using a non-parametric test and try to transform the data

## -----------------------------------------------------------------
## 
## Significant interaction: analyzing the interaction
## 
## -----------------------------------------------------------------
## 
## -----------------------------------------------------------------
## Analyzing  F1  inside of each level of  F2
## -----------------------------------------------------------------
##                          Df Sum Sq Mean Sq F value    Pr(>F)    
## bloco                     4  11614    2903  0.6551 0.6282168    
## Fator2                    3 116555   38852  8.7660 0.0002934 ***
## Fator2:Fator1             4 468257  117064 26.4129 3.786e-09 ***
##   Fator2:Fator1: Plantio  1  26112   26112  5.8916 0.0218981 *  
##   Fator2:Fator1: V1+15    1 258888  258888 58.4123 2.518e-08 ***
##   Fator2:Fator1: V3+15    1 112360  112360 25.3515 2.520e-05 ***
##   Fator2:Fator1: R1+15    1  70896   70896 15.9962 0.0004207 ***
## Residuals                28 124098    4432                      
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## -----------------------------------------------------------------
## Analyzing  F2  inside of the level of  F1
## -----------------------------------------------------------------
## 
##                     Df Sum Sq Mean Sq F value    Pr(>F)    
## bloco                4  11614    2903  0.6551  0.628217    
## Fator1               1  16160   16160  3.6462  0.066491 .  
## Fator1:Fator2        6 568651   94775 21.3839 2.917e-09 ***
##   Fator1:Fator2: IN  3  75470   25157  5.6760  0.003625 ** 
##   Fator1:Fator2: NI  3 493181  164394 37.0917 6.882e-10 ***
## Residuals           28 124098    4432                      
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## -----------------------------------------------------------------
## Final table
## -----------------------------------------------------------------
##     Plantio    V1+15    V3+15     R1+15
## IN 272.8 aA 140.4 bB 304.0 aA 236.6 aAB
## NI 170.6 bB 462.2 aA  92.0 bB   68.2 bB
## 
## 
## Averages followed by the same lowercase letter in the column 
## and uppercase in the row do not differ by the tukey (p< 0.05 )

11.4 FAT2DIC.ad

data(cloro)
respAd=c(268, 322, 275, 350, 320)
with(cloro,FAT2DIC.ad(f1, f2, bloco, resp, respAd, ylab="Number of nodules", legend = "Stages"))
## 
## -----------------------------------------------------------------
## Normality of errors
## -----------------------------------------------------------------
##                          Method Statistic   p.value
##  Shapiro-Wilk normality test(W) 0.9680878 0.3125183
## As the calculated p-value is greater than the 5% significance level, hypothesis H0 is not rejected. Therefore, errors can be considered normal
## 
## -----------------------------------------------------------------
## Homogeneity of Variances
## -----------------------------------------------------------------
##                               Method Statistic   p.value
##  Bartlett test(Bartlett's K-squared)  9.875441 0.1957427
## As the calculated p-value is greater than the 5% significance level, hypothesis H0 is not rejected. Therefore, the variances can be considered homogeneous
## 
## -----------------------------------------------------------------
## Independence from errors
## -----------------------------------------------------------------
##                  Method Statistic   p.value
##  Durbin-Watson test(DW)  2.092504 0.1892105
## As the calculated p-value is greater than the 5% significance level, hypothesis H0 is not rejected. Therefore, errors can be considered independent
## 
## -----------------------------------------------------------------
## Additional Information
## -----------------------------------------------------------------
## 
## CV (%) =  27.38
## Mean Factorial =  218.35
## Median Factorial =  185
## Mean Aditional =  307
## Median Aditional =  320
## Possible outliers =  No discrepant point
## 
## -----------------------------------------------------------------
## Analysis of Variance
## -----------------------------------------------------------------
##                Df   Sum Sq    Mean.Sq   F value        Pr(F)
## Fator1          1  16160.4  16160.400  4.140743 4.927778e-02
## Fator2          3 116554.5  38851.500  9.954833 6.428916e-05
## Fator1:Fator2   3 452096.2 150698.733 38.613199 2.411216e-11
## Ad x Factorial  1  34928.1  34928.100  8.949549 4.985733e-03
## Residuals      36 140500.0   3902.778
## 

## -----------------------------------------------------------------
## Significant interaction: analyzing the interaction
## -----------------------------------------------------------------
##                          Df Sum Sq Mean Sq F value    Pr(>F)    
## Fator2                    3 116555   38852  9.9548 6.429e-05 ***
## Fator2:Fator1             4 468257  117064 29.9951 5.126e-11 ***
##   Fator2:Fator1: Plantio  1  26112   26112  6.6906 0.0138814 *  
##   Fator2:Fator1: V1+15    1 258888  258888 66.3343 1.101e-09 ***
##   Fator2:Fator1: V3+15    1 112360  112360 28.7898 4.897e-06 ***
##   Fator2:Fator1: R1+15    1  70896   70896 18.1656 0.0001393 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## -----------------------------------------------------------------
## Analyzing  F2  inside of the level of  F1
## -----------------------------------------------------------------
## 
##                     Df Sum Sq Mean Sq F value    Pr(>F)    
## Fator1               1  16160   16160  4.1407  0.049278 *  
## Fator1:Fator2        6 568651   94775 24.2840 2.774e-11 ***
##   Fator1:Fator2: IN  3  75470   25157  6.4458  0.001317 ** 
##   Fator1:Fator2: NI  3 493181  164394 42.1222 7.282e-12 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## -----------------------------------------------------------------
## Final table
## -----------------------------------------------------------------
##     Plantio    V1+15    V3+15     R1+15
## IN 272.8 aA 140.4 bB 304.0 aA 236.6 aAB
## NI 170.6 bB 462.2 aA  92.0 bB   68.2 bB
## 
## 
## Averages followed by the same lowercase letter in the column and 
## uppercase in the row do not differ by the tukey (p< 0.05 )

11.5 FAT2DBC.ad

data(cloro)
respAd=c(268, 322, 275, 350, 320)
with(cloro,
     FAT2DBC.ad(f1, f2, bloco, resp, respAd, ylab="Number of nodules", legend = "Stages"))
## 
## -----------------------------------------------------------------
## Normality of errors
## -----------------------------------------------------------------
##                          Method Statistic   p.value
##  Shapiro-Wilk normality test(W) 0.9548911 0.1117923
## As the calculated p-value is greater than the 5% significance level, hypothesis H0 is not rejected. Therefore, errors can be considered normal
## 
## -----------------------------------------------------------------
## Homogeneity of Variances
## -----------------------------------------------------------------
##                               Method Statistic    p.value
##  Bartlett test(Bartlett's K-squared)  16.11086 0.02412261
## As the calculated p-value is less than the 5% significance level, H0 is rejected. Therefore, the variances are not homogeneous
## 
## -----------------------------------------------------------------
## Independence from errors
## -----------------------------------------------------------------
##                  Method Statistic   p.value
##  Durbin-Watson test(DW)  2.047899 0.1769663
## As the calculated p-value is greater than the 5% significance level, hypothesis H0 is not rejected. Therefore, errors can be considered independent
## 
## -----------------------------------------------------------------
## Additional Information
## -----------------------------------------------------------------
## 
## CV (%) =  27.38
## Mean Factorial =  218.35
## Median Factorial =  185
## Mean Aditional =  307
## Median Aditional =  320
## Possible outliers =  No discrepant point
## 
## -----------------------------------------------------------------
## Analysis of Variance
## -----------------------------------------------------------------
##                Df   Sum Sq    Mean.Sq     F value        Pr(F)
## Fator1          1  16160.4  16160.400   4.1407431 4.927778e-02
## Fator2          3 116554.5  38851.500   9.9548327 6.428916e-05
## block           4  11613.6   2903.400   0.7439317 5.684322e-01
## Fator1:Fator2   3 452096.2 150698.733  38.6131986 2.411216e-11
## Ad x Factorial  1 475410.7 475410.700 121.8134178 4.174439e-13
## Residuals      36 140500.0   3902.778
## 
## Your analysis is not valid, suggests using a non-parametric test and try to transform the data
## 

## -----------------------------------------------------------------
## Significant interaction: analyzing the interaction
## -----------------------------------------------------------------
##                          Df Sum Sq Mean Sq F value    Pr(>F)    
## Fator2                    3 116555   38852  9.9548 6.429e-05 ***
## block                     4  11614    2903  0.7439 0.5684322    
## Fator2:Fator1             4 468257  117064 29.9951 5.126e-11 ***
##   Fator2:Fator1: Plantio  1  26112   26112  6.6906 0.0138814 *  
##   Fator2:Fator1: V1+15    1 258888  258888 66.3343 1.101e-09 ***
##   Fator2:Fator1: V3+15    1 112360  112360 28.7898 4.897e-06 ***
##   Fator2:Fator1: R1+15    1  70896   70896 18.1656 0.0001393 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## -----------------------------------------------------------------
## Analyzing  F2  inside of the level of  F1
## -----------------------------------------------------------------
## 
##                     Df Sum Sq Mean Sq F value    Pr(>F)    
## Fator1               1  16160   16160  4.1407  0.049278 *  
## block                4  11614    2903  0.7439  0.568432    
## Fator1:Fator2        6 568651   94775 24.2840 2.774e-11 ***
##   Fator1:Fator2: IN  3  75470   25157  6.4458  0.001317 ** 
##   Fator1:Fator2: NI  3 493181  164394 42.1222 7.282e-12 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## -----------------------------------------------------------------
## Final table
## -----------------------------------------------------------------
##     Plantio    V1+15    V3+15     R1+15
## IN 272.8 aA 140.4 bB 304.0 aA 236.6 aAB
## NI 170.6 bB 462.2 aA  92.0 bB   68.2 bB
## 
## 
## Averages followed by the same lowercase letter in the column and 
## uppercase in the row do not differ by the tukey (p< 0.05 )

11.6 FAT2DIC.art

data(cloro)
with(cloro, FAT2DIC.art(f1,f2,resp))
## 
## -----------------------------------------------------------------
## Analysis of Variance of Aligned Rank Transformed Data
## -----------------------------------------------------------------
##                          FV Df Df.res     SQ  SQres    Fvalue      p-value
## fator1               fator1  1     32  640.0 4642.0  4.411891 4.365822e-02
## fator2               fator2  3     32 2570.2 2745.8  9.984510 8.493625e-05
## fator1:fator2 fator1:fator2  3     32 4103.8 1199.2 36.502557 1.916135e-10
## 
## 
## -----------------------------------------------------------------
##   fator1  fator2 emmean     SE df  lower.CL  upper.CL .group
## 2     IN Plantio   25.0 2.7377 32 19.423488 30.576512      A
## 1     NI Plantio   17.8 2.7377 32 12.223488 23.376512      A
## 4     IN   R1+15   27.6 2.7377 32 22.023488 33.176512     A 
## 3     NI   R1+15   14.4 2.7377 32  8.823488 19.976512      B
## 5     NI   V1+15   36.8 2.7377 32 31.223488 42.376512     A 
## 6     IN   V1+15    3.0 2.7377 32 -2.576512  8.576512      B
## 8     IN   V3+15   28.0 2.7377 32 22.423488 33.576512     A 
## 7     NI   V3+15   11.4 2.7377 32  5.823488 16.976512      B
## 
## 
## -----------------------------------------------------------------
##    fator2 fator1 emmean     SE df  lower.CL  upper.CL .group
## 3   V3+15     IN   28.0 2.7377 32 22.423488 33.576512     a 
## 1   R1+15     IN   27.6 2.7377 32 22.023488 33.176512     a 
## 2 Plantio     IN   25.0 2.7377 32 19.423488 30.576512     a 
## 4   V1+15     IN    3.0 2.7377 32 -2.576512  8.576512      b
## 8   V1+15     NI   36.8 2.7377 32 31.223488 42.376512     a 
## 6 Plantio     NI   17.8 2.7377 32 12.223488 23.376512      b
## 5   R1+15     NI   14.4 2.7377 32  8.823488 19.976512      b
## 7   V3+15     NI   11.4 2.7377 32  5.823488 16.976512      b
## Warning in mean.default(mean): argumento não é numérico nem lógico: retornando
## NA
## Warning: Removed 8 rows containing missing values (geom_label).

11.7 FAT2DBC.art

data(cloro)
with(cloro,FAT2DBC.art(f1,f2,bloco,resp))
## boundary (singular) fit: see ?isSingular
## boundary (singular) fit: see ?isSingular
## boundary (singular) fit: see ?isSingular
## boundary (singular) fit: see ?isSingular
## boundary (singular) fit: see ?isSingular
## boundary (singular) fit: see ?isSingular
## 
## -----------------------------------------------------------------
## Analysis of Variance of Aligned Rank Transformed Data
## -----------------------------------------------------------------
## boundary (singular) fit: see ?isSingular
## boundary (singular) fit: see ?isSingular
## boundary (singular) fit: see ?isSingular
##                          FV         F Df Df.res      p-value
## fator1               fator1  4.411891  1     28 4.482053e-02
## fator2               fator2  9.984510  3     28 1.212358e-04
## fator1:fator2 fator1:fator2 36.502557  3     28 8.217384e-10
## boundary (singular) fit: see ?isSingular
## boundary (singular) fit: see ?isSingular
## boundary (singular) fit: see ?isSingular
## boundary (singular) fit: see ?isSingular
## 
## 
## -----------------------------------------------------------------
##   fator1  fator2 emmean     SE df  lower.CL  upper.CL .group
## 2     IN Plantio   25.0 2.7377 32 19.423488 30.576512      A
## 1     NI Plantio   17.8 2.7377 32 12.223488 23.376512      A
## 4     IN   R1+15   27.6 2.7377 32 22.023488 33.176512     A 
## 3     NI   R1+15   14.4 2.7377 32  8.823488 19.976512      B
## 5     NI   V1+15   36.8 2.7377 32 31.223488 42.376512     A 
## 6     IN   V1+15    3.0 2.7377 32 -2.576512  8.576512      B
## 8     IN   V3+15   28.0 2.7377 32 22.423488 33.576512     A 
## 7     NI   V3+15   11.4 2.7377 32  5.823488 16.976512      B
## 
## 
## -----------------------------------------------------------------
##    fator2 fator1 emmean     SE df  lower.CL  upper.CL .group
## 3   V3+15     IN   28.0 2.7377 32 22.423488 33.576512     a 
## 1   R1+15     IN   27.6 2.7377 32 22.023488 33.176512     a 
## 2 Plantio     IN   25.0 2.7377 32 19.423488 30.576512     a 
## 4   V1+15     IN    3.0 2.7377 32 -2.576512  8.576512      b
## 8   V1+15     NI   36.8 2.7377 32 31.223488 42.376512     a 
## 6 Plantio     NI   17.8 2.7377 32 12.223488 23.376512      b
## 5   R1+15     NI   14.4 2.7377 32  8.823488 19.976512      b
## 7   V3+15     NI   11.4 2.7377 32  5.823488 16.976512      b