[R-es] Comparaciones múltiples

[Javier Villacampa González]

Hola Miguel yo tengo una función para hacer comparaciones multiples ( muy
util si hacer medidas repetidas, ya que en el otro caso tienes la función
HSD)

t.test.Comparison.Function.Ch <- function( data, StringResponse,
StringFactor){
  ############################
  # Factor
  ############################
  data[,StringFactor ] <- factor(data[,StringFactor ] )

  ############################
  # Create data.frame
  ############################
  T.Test <- data.frame(Name = NA, LevelOne =NA, LevelTwo= NA,statistic =
NA, df = NA, df = NA, p.value = NA )
  T.Test <- T.Test[-1,]
  NumberOfFactors <- length(levels(data[, StringFactor]) )

  ############################
  # t.test computation
  ############################
  for(i in 1:(  NumberOfFactors - 1 ) ){
    LevelOne <- levels(data[, StringFactor])[i]
    for(j in (i+1):( NumberOfFactors) ){
      LevelTwo <- levels(data[, StringFactor])[j]
      x <-t.test( x =data[data[, StringFactor] == LevelOne, StringResponse]
,
                  y =data[data[, StringFactor] == LevelTwo, StringResponse]
)

      T.Test <- rbind( T.Test,
                       data.frame(Name = paste(LevelOne,LevelTwo, sep= "."),
                                  LevelOne = LevelOne,
                                  LevelTwo= LevelTwo,
                                  statistic = x$statistic, df =
x$parameter, p.value = x$p.value )
      )
    }
  }

  ############################
  # Significacion
  ############################
  T.Test$Sign <- "n.s."
  if(dim( T.Test[  T.Test$p.value <= 0.1 & T.Test$p.value > 0.05 ,] )[1] >
0 ){
    T.Test[  T.Test$p.value <= 0.1 & T.Test$p.value > 0.05 ,]$Sign <- "·"
  }

  if(dim( T.Test[  T.Test$p.value <= 0.05 & T.Test$p.value > 0.01 ,] )[1] >
0 ){
    T.Test[  T.Test$p.value <= 0.05 & T.Test$p.value > 0.01 ,]$Sign <- "*"
  }

  if(dim( T.Test[  T.Test$p.value <= 0.01 & T.Test$p.value > 0.001 ,] )[1]
> 0 ){
    T.Test[  T.Test$p.value <= 0.01 & T.Test$p.value > 0.001 ,]$Sign <- "**"
  }

  if(dim( T.Test[  T.Test$p.value <= 0.001 ,] )[1] > 0 ){
    T.Test[  T.Test$p.value <= 0.001  ,]$Sign <- "***"
  }

  ############################
  # Bonferroni p.value
  ############################
  T.Test$p.value.Adjusted <- p.adjust(T.Test$p.value, method = "bonferroni")

  ############################
  # Significacion
  ############################
  T.Test$Sign.Adjusted <- "n.s."
  if(dim( T.Test[  T.Test$p.value.Adjusted <= 0.1 & T.Test$p.value.Adjusted
> 0.05 ,] )[1] > 0 ){
    T.Test[  T.Test$p.value.Adjusted <= 0.1 & T.Test$p.value.Adjusted >
0.05 ,]$Sign.Adjusted <- "·"
  }

  if(dim( T.Test[  T.Test$p.value.Adjusted <= 0.05 &
T.Test$p.value.Adjusted > 0.01 ,] )[1] > 0 ){
    T.Test[  T.Test$p.value.Adjusted <= 0.05 & T.Test$p.value.Adjusted >
0.01 ,]$Sign.Adjusted <- "*"
  }

  if(dim( T.Test[  T.Test$p.value.Adjusted <= 0.01 &
T.Test$p.value.Adjusted > 0.001 ,] )[1] > 0 ){
    T.Test[  T.Test$p.value.Adjusted <= 0.01 & T.Test$p.value.Adjusted >
0.001 ,]$Sign.Adjusted <- "**"
  }

  if(dim( T.Test[  T.Test$p.value.Adjusted <= 0.001 ,] )[1] > 0 ){
    T.Test[  T.Test$p.value.Adjusted <= 0.001  ,]$Sign.Adjusted <- "***"
  }


  ############################
  # Effect Size
  ############################
  t <- T.Test$statistic
  df <-T.Test$df
  T.Test$Effect.Size <- sqrt( t^2/(t^2+df) )

  T.Test$statistic <- round( T.Test$statistic, digits = 3)
  T.Test$df <- round( T.Test$df, digits = 3)
  T.Test$p.value <- round( T.Test$p.value, digits = 3)
  T.Test$p.value.Adjusted <- round( T.Test$p.value.Adjusted, digits = 3)
  T.Test$Effect.Size <- round( T.Test$Effect.Size, digits = 3)


  return(T.Test)


}


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