#Diseño 1: Factorial simple en arreglo completamemte al azar.

#Único factor 
#Sin razón para bloquear 


#Imaginado del experimento en el campo: Creamos un dataframe a partir de todas las combinaciones posibles de la variable FACTOR

xy = expand.grid(x = seq(0,5), y = seq(0,5))
plot(xy, pch = 15, cex = 3, asp = 1)

#FACTOR
genotipo = gl(n = 6, k = 6, length = 36,
              labels= paste0("gen", 1:6))

#VARIABLE RESPUESTA 
set.seed(123)
PS= c(
  rnorm(12, 1200, 100),
  rnorm(12, 1500, 80),
  rnorm(12, 1420, 90)
)

aleat=sample(36)
datos= data.frame(xy[aleat,], genotipo, PS)
head(datos)
##    x y genotipo       PS
## 15 2 2     gen1 1143.952
## 26 1 4     gen1 1176.982
## 31 0 5     gen1 1355.871
## 16 3 2     gen1 1207.051
## 20 1 3     gen1 1212.929
## 30 5 4     gen1 1371.506
library(ggplot2) 

ggplot(datos)+
  aes(x,y, fill = genotipo)+
  geom_tile()

#Análisis descriptivo 

ggplot(datos)+
  aes(genotipo, PS)+
  geom_boxplot()

ggplot(datos)+
  aes(genotipo, PS)+
  geom_violin()

#Análisis inferencial

\[H_0: \mu_{g_1}= \mu_{g_2}= \mu_{g_3}= \mu_{g_4}= \mu_{g_5}= \mu_{g_6}\\ H_a: H_0\text{ es falsa}\]

Modelo

\[y_{i j} = \mu_i + \epsilon_{ij}\\ i=1,2,3,4,5,6~; j=1,2,3,4,5,6\]

\[y-{ij} = \text{Peso seco i-esimo genotipo y j-isema repetición}\] \[\mu:_i=\text{ La media de cada i_esimo genotipo}\] \[\epsilon_{i} = \text{residuals}\]

Modelo en forma de efectos

\[y_{ij} = \mu + \tau_i + \epsilon{ij} \] \(\mu\) media global \(\tau_i\) efecto de cada genotipo

modelo en forma matricial

\[Y = X\beta + E \] \(X\) matriz del diseño 36 filas y 7 columnas (1 columna representa la media y las 6 restantes una por genotipo)

\(\beta\) vector de parametros (\[{\mu; \tau_1; \tau_2; \tau_3; \tau_4; \tau_5; \tau_6}\])

\[H_0:\tau_1=\tau_2= \tau_3= \tau_4= \tau_5= \tau_6=0 \]

mod1 = aov(PS ~ genotipo, data =datos)
smod1 = summary(mod1)
pv1 = smod1[[1]][1,5]

ifelse(pv1 < 0.05, 'Rechazo Ho', 'No rechazo Ho')
## [1] "Rechazo Ho"

#Como el valor de F es 14.22, la variabilidad causada por los genotipos es 14.22 veces más grande que la causada por el error.

#p-value: Se rechaza la hipótesis nula, lo que sugiere que existen diferencias en al menos uno de los tratamientos en cuánto al peso seco.

#ESTIMANDO LOS EFECTOS

#Media global 
mu = mean(datos$PS)
#Media por genotipo  
mu_i = tapply(datos$PS, datos$genotipo, mean)
#Efecto por genotipo
tau_i = mu_i - mu
tau_i
##       gen1       gen2       gen3       gen4       gen5       gen6 
## -134.97483 -185.56951  123.96002   82.81483   22.23648   91.53300
boxplot(PS ~ genotipo, datos, ylim=c(1000, 1800), las=1)
points(1:6, mu_i, pch=16, col='red')
abline(h = mu, lty=2, col='red')
segments(1:6-.2, mu_i, 1:6-.2, mu, col='blue', lwd=2, lty=2)
text(1:6, rep(1700,6), round(tau_i, 2))
text(1:6, rep(1000,6), round(tau_i, 2))

#REVISIÓN DE SUPUESTOS \[H_O: \sigma^2_{g1}=\sigma^2_{g2}=\sigma^2_{g3}=\sigma^2_{g4}=\sigma^2_{g5}=\sigma^2_{g6}\]

\[H_O:\epsilon \sim N(0, \sigma^2_e)\]

#VARIANZA:

hist(mod1$residuals)

var_res = tapply(mod1$residuals, datos$genotipo, var)

# Igualdad de varianzas
bartlett.test(mod1$residuals, datos$genotipo)
## 
##  Bartlett test of homogeneity of variances
## 
## data:  mod1$residuals and datos$genotipo
## Bartlett's K-squared = 5.5895, df = 5, p-value = 0.3482
#Normalidad de residuos
shapiro.test(mod1$residuals)
## 
##  Shapiro-Wilk normality test
## 
## data:  mod1$residuals
## W = 0.97311, p-value = 0.5164

#Como el p-value en la prueba de igualdad de varianzas es mayor al 5% estadisticamente se pueden considerar iguales. Como el p-value en la prueba de normalidad es 51.64% (> 5%) se considera que los residuales siguen una distribución normal

#COMPARACIÓN DE MEDIAS POSTERIOR AL ANÁLISIS DE VARIANZA

#Prueba de máxima diferencia de Tukeypar(mar=c(4, 6, 3, 1))
tt = TukeyHSD(mod1, 'genotipo')
plot(tt, las=1)
abline(v=0, lty=2, col='red',lwd=2)

tt
##   Tukey multiple comparisons of means
##     95% family-wise confidence level
## 
## Fit: aov(formula = PS ~ genotipo, data = datos)
## 
## $genotipo
##                  diff         lwr       upr     p adj
## gen2-gen1  -50.594675 -198.214230  97.02488 0.8995877
## gen3-gen1  258.934855  111.315300 406.55441 0.0001225
## gen4-gen1  217.789664   70.170110 365.40922 0.0012678
## gen5-gen1  157.211312    9.591757 304.83087 0.0316170
## gen6-gen1  226.507827   78.888272 374.12738 0.0007764
## gen3-gen2  309.529530  161.909976 457.14908 0.0000068
## gen4-gen2  268.384340  120.764785 416.00389 0.0000713
## gen5-gen2  207.805987   60.186433 355.42554 0.0022109
## gen6-gen2  277.102502  129.482947 424.72206 0.0000433
## gen4-gen3  -41.145191 -188.764745 106.47436 0.9557570
## gen5-gen3 -101.723543 -249.343098  45.89601 0.3163216
## gen6-gen3  -32.427028 -180.046583 115.19253 0.9841426
## gen5-gen4  -60.578352 -208.197907  87.04120 0.8096942
## gen6-gen4    8.718162 -138.901392 156.33772 0.9999711
## gen6-gen5   69.296515  -78.323040 216.91607 0.7103650
library(agricolae)
dt = duncan.test(mod1, 'genotipo', console = T)
## 
## Study: mod1 ~ "genotipo"
## 
## Duncan's new multiple range test
## for PS 
## 
## Mean Square Error:  7066.534 
## 
## genotipo,  means
## 
##            PS       std r      Min      Max
## gen1 1244.715  95.50024 6 1143.952 1371.506
## gen2 1194.121  90.44675 6 1073.494 1322.408
## gen3 1503.650  99.77789 6 1342.671 1642.953
## gen4 1462.505  52.69259 6 1414.574 1556.108
## gen5 1401.927 103.29604 6 1268.198 1532.843
## gen6 1471.223  41.18360 6 1393.444 1500.561
## 
## Alpha: 0.05 ; DF Error: 30 
## 
## Critical Range
##         2         3         4         5         6 
##  99.11886 104.16376 107.43409 109.76839 111.53078 
## 
## Means with the same letter are not significantly different.
## 
##            PS groups
## gen3 1503.650      a
## gen6 1471.223      a
## gen4 1462.505      a
## gen5 1401.927      a
## gen1 1244.715      b
## gen2 1194.121      b
plot(dt)

#DISEÑO NÚMERO 1. INCUMPLIENDO SUPUESTOS.

# Único factor
# Sin razón de bloquear

xy = expand.grid(x = seq(0,5), y = seq(0,5))
plot(xy, pch = 15, cex = 3, asp = 1)

genotipo = gl(n = 6, k = 6, length = 36,
              labels = paste0('gen', 1:6))
genotipo
##  [1] gen1 gen1 gen1 gen1 gen1 gen1 gen2 gen2 gen2 gen2 gen2 gen2 gen3 gen3 gen3
## [16] gen3 gen3 gen3 gen4 gen4 gen4 gen4 gen4 gen4 gen5 gen5 gen5 gen5 gen5 gen5
## [31] gen6 gen6 gen6 gen6 gen6 gen6
## Levels: gen1 gen2 gen3 gen4 gen5 gen6
#Variable respuesta
set.seed(123)
PS = c(
  rnorm(12, 1200, 120),
  rnorm(12, 1500, 100),
  rnorm(12, 1420, 250)
)
datos = data.frame(xy[aleat,], genotipo, PS)
head(datos)
##    x y genotipo       PS
## 15 2 2     gen1 1132.743
## 26 1 4     gen1 1172.379
## 31 0 5     gen1 1387.045
## 16 3 2     gen1 1208.461
## 20 1 3     gen1 1215.515
## 30 5 4     gen1 1405.808
ggplot(datos)+
  aes(genotipo, PS)+
  geom_boxplot()

mod1b = aov(PS~genotipo, datos)
smod1b = summary(mod1b)
smod1b
##             Df Sum Sq Mean Sq F value  Pr(>F)   
## genotipo     5 627712  125542   5.372 0.00121 **
## Residuals   30 701126   23371                   
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
shapiro.test(mod1b$residuals)
## 
##  Shapiro-Wilk normality test
## 
## data:  mod1b$residuals
## W = 0.98349, p-value = 0.8558
bartlett.test(mod1b$residuals, datos$genotipo)
## 
##  Bartlett test of homogeneity of variances
## 
## data:  mod1b$residuals and datos$genotipo
## Bartlett's K-squared = 12.401, df = 5, p-value = 0.02969

Se rechaza la hipótesis de igualdad de varianzas, se incumple el supuesto y esto complica la interpretación

#ANÁLISIS DE VARIANZA PARA UN DISEÑO FACTORIAL SIMPLE EN ARREGLO COMPLETAMENTE AL AZAR, EN PRESENCIA DE HETEROCEDASTICIDAD

mod1c = oneway.test(PS~genotipo, datos)
mod1c
## 
##  One-way analysis of means (not assuming equal variances)
## 
## data:  PS and genotipo
## F = 8.6764, num df = 5.000, denom df = 13.702, p-value = 0.0006918

Cuando se incumple normalidad e igualdad de varianzas, entonces…

Análisis de varianza no parametrico para un diseño en arreglo factorial simple en arreglo completamente al azar

#Prueba de Kruskal-Walles –> Cuando no se cumplen dos supuestos. Solo es válido para este experimento

\[H_0: R_1=R_2=R_3=R_4=R_5=R_6\]

mod1d = kruskal.test(PS, genotipo)
mod1d
## 
##  Kruskal-Wallis rank sum test
## 
## data:  PS and genotipo
## Kruskal-Wallis chi-squared = 17.204, df = 5, p-value = 0.004128

comparacion de rangos promedios posterior a kruskal. wallis

#library(PMCMR)
#posthoc.kruskal.nemeyi.test(PS, genotipo)
library(PMCMRplus)



library(FSA)
## ## FSA v0.9.4. See citation('FSA') if used in publication.
## ## Run fishR() for related website and fishR('IFAR') for related book.
dunnTest(PS, genotipo)
## Dunn (1964) Kruskal-Wallis multiple comparison
##   p-values adjusted with the Holm method.
##     Comparison          Z      P.unadj      P.adj
## 1  gen1 - gen2  0.4383973 0.6610983037 0.66109830
## 2  gen1 - gen3 -2.3563855 0.0184537565 0.22144508
## 3  gen2 - gen3 -2.7947828 0.0051934597 0.06751498
## 4  gen1 - gen4 -1.8357887 0.0663889146 0.66388915
## 5  gen2 - gen4 -2.2741860 0.0229548062 0.25250287
## 6  gen3 - gen4  0.5205968 0.6026476838 1.00000000
## 7  gen1 - gen5 -1.2603922 0.2075279011 1.00000000
## 8  gen2 - gen5 -1.6987895 0.0893588460 0.80422961
## 9  gen3 - gen5  1.0959932 0.2730817290 1.00000000
## 10 gen4 - gen5  0.5753965 0.5650232007 1.00000000
## 11 gen1 - gen6 -2.8769823 0.0040149814 0.05620974
## 12 gen2 - gen6 -3.3153796 0.0009151876 0.01372781
## 13 gen3 - gen6 -0.5205968 0.6026476838 1.00000000
## 14 gen4 - gen6 -1.0411936 0.2977857118 1.00000000
## 15 gen5 - gen6 -1.6165900 0.1059668029 0.84773442
rangos = rank(PS, ties.method = "average")
rangos
##  [1]  4  7 16  8  9 19 11  2  3  6 15 10 27 25 21 35 28 13 29 22 17 24 18 20 12
## [26]  1 32 23  5 36 26 14 34 33 31 30
boxplot(rangos ~ genotipo)

ANÁLISIS VARIANZA PERMUTACIONAL

library(RVAideMemoire)
## *** Package RVAideMemoire v 0.9-81-2 ***
## 
## Attaching package: 'RVAideMemoire'
## The following object is masked from 'package:FSA':
## 
##     se
perm.anova(PS ~ genotipo, data = datos, nperm =10000)
## 
  |                                                                            
  |                                                                      |   0%
  |                                                                            
  |=                                                                     |   1%
  |                                                                            
  |=                                                                     |   2%
  |                                                                            
  |==                                                                    |   3%
  |                                                                            
  |===                                                                   |   4%
  |                                                                            
  |====                                                                  |   5%
  |                                                                            
  |====                                                                  |   6%
  |                                                                            
  |=====                                                                 |   7%
  |                                                                            
  |======                                                                |   8%
  |                                                                            
  |======                                                                |   9%
  |                                                                            
  |=======                                                               |  10%
  |                                                                            
  |========                                                              |  11%
  |                                                                            
  |========                                                              |  12%
  |                                                                            
  |=========                                                             |  13%
  |                                                                            
  |==========                                                            |  14%
  |                                                                            
  |==========                                                            |  15%
  |                                                                            
  |===========                                                           |  16%
  |                                                                            
  |============                                                          |  17%
  |                                                                            
  |=============                                                         |  18%
  |                                                                            
  |=============                                                         |  19%
  |                                                                            
  |==============                                                        |  20%
  |                                                                            
  |===============                                                       |  21%
  |                                                                            
  |===============                                                       |  22%
  |                                                                            
  |================                                                      |  23%
  |                                                                            
  |=================                                                     |  24%
  |                                                                            
  |==================                                                    |  25%
  |                                                                            
  |==================                                                    |  26%
  |                                                                            
  |===================                                                   |  27%
  |                                                                            
  |====================                                                  |  28%
  |                                                                            
  |====================                                                  |  29%
  |                                                                            
  |=====================                                                 |  30%
  |                                                                            
  |======================                                                |  31%
  |                                                                            
  |======================                                                |  32%
  |                                                                            
  |=======================                                               |  33%
  |                                                                            
  |========================                                              |  34%
  |                                                                            
  |========================                                              |  35%
  |                                                                            
  |=========================                                             |  36%
  |                                                                            
  |==========================                                            |  37%
  |                                                                            
  |===========================                                           |  38%
  |                                                                            
  |===========================                                           |  39%
  |                                                                            
  |============================                                          |  40%
  |                                                                            
  |=============================                                         |  41%
  |                                                                            
  |=============================                                         |  42%
  |                                                                            
  |==============================                                        |  43%
  |                                                                            
  |===============================                                       |  44%
  |                                                                            
  |================================                                      |  45%
  |                                                                            
  |================================                                      |  46%
  |                                                                            
  |=================================                                     |  47%
  |                                                                            
  |==================================                                    |  48%
  |                                                                            
  |==================================                                    |  49%
  |                                                                            
  |===================================                                   |  50%
  |                                                                            
  |====================================                                  |  51%
  |                                                                            
  |====================================                                  |  52%
  |                                                                            
  |=====================================                                 |  53%
  |                                                                            
  |======================================                                |  54%
  |                                                                            
  |======================================                                |  55%
  |                                                                            
  |=======================================                               |  56%
  |                                                                            
  |========================================                              |  57%
  |                                                                            
  |=========================================                             |  58%
  |                                                                            
  |=========================================                             |  59%
  |                                                                            
  |==========================================                            |  60%
  |                                                                            
  |===========================================                           |  61%
  |                                                                            
  |===========================================                           |  62%
  |                                                                            
  |============================================                          |  63%
  |                                                                            
  |=============================================                         |  64%
  |                                                                            
  |==============================================                        |  65%
  |                                                                            
  |==============================================                        |  66%
  |                                                                            
  |===============================================                       |  67%
  |                                                                            
  |================================================                      |  68%
  |                                                                            
  |================================================                      |  69%
  |                                                                            
  |=================================================                     |  70%
  |                                                                            
  |==================================================                    |  71%
  |                                                                            
  |==================================================                    |  72%
  |                                                                            
  |===================================================                   |  73%
  |                                                                            
  |====================================================                  |  74%
  |                                                                            
  |====================================================                  |  75%
  |                                                                            
  |=====================================================                 |  76%
  |                                                                            
  |======================================================                |  77%
  |                                                                            
  |=======================================================               |  78%
  |                                                                            
  |=======================================================               |  79%
  |                                                                            
  |========================================================              |  80%
  |                                                                            
  |=========================================================             |  81%
  |                                                                            
  |=========================================================             |  82%
  |                                                                            
  |==========================================================            |  83%
  |                                                                            
  |===========================================================           |  84%
  |                                                                            
  |============================================================          |  85%
  |                                                                            
  |============================================================          |  86%
  |                                                                            
  |=============================================================         |  87%
  |                                                                            
  |==============================================================        |  88%
  |                                                                            
  |==============================================================        |  89%
  |                                                                            
  |===============================================================       |  90%
  |                                                                            
  |================================================================      |  91%
  |                                                                            
  |================================================================      |  92%
  |                                                                            
  |=================================================================     |  93%
  |                                                                            
  |==================================================================    |  94%
  |                                                                            
  |==================================================================    |  95%
  |                                                                            
  |===================================================================   |  96%
  |                                                                            
  |====================================================================  |  97%
  |                                                                            
  |===================================================================== |  98%
  |                                                                            
  |===================================================================== |  99%
  |                                                                            
  |======================================================================| 100%
## Permutation Analysis of Variance Table
## 
## Response: PS
## 10000 permutations
##           Sum Sq Df Mean Sq F value Pr(>F)   
## genotipo  627712  5  125542  5.3717 0.0013 **
## Residuals 701126 30   23371                  
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1