set.seed(2022)
fumagina =round(runif(n = 80 ,
min = 0.35,
max = 1),0)
table(fumagina)[1]/sum(table(fumagina))*100
## 0
## 22.5
pr2 = prop.test(x = table(fumagina)[1],
n = 80,
p = 0.05,alternative = "g")
## Warning in prop.test(x = table(fumagina)[1], n = 80, p = 0.05, alternative =
## "g"): Chi-squared approximation may be incorrect
ifelse(pr2$p.value<0.05,
"Rechazo Ho",
"No rechazo Ho")
## [1] "Rechazo Ho"
set.seed(132)
brix = c(rnorm(60, 16, 1.5),
rnorm(60, 18, 1.5))
var = gl(2, 60, 120, c('VR1', 'VR2'))
data = data.frame(brix, var)
head(data)
## brix var
## 1 16.71117 VR1
## 2 15.16758 VR1
## 3 15.98506 VR1
## 4 17.60049 VR1
## 5 14.93166 VR1
## 6 15.51900 VR1
boxplot(data$brix~data$var)
library(vioplot)
## Warning: package 'vioplot' was built under R version 4.2.2
## Loading required package: sm
## Warning: package 'sm' was built under R version 4.2.2
## Package 'sm', version 2.2-5.7: type help(sm) for summary information
## Loading required package: zoo
## Warning: package 'zoo' was built under R version 4.2.2
##
## Attaching package: 'zoo'
## The following objects are masked from 'package:base':
##
## as.Date, as.Date.numeric
vioplot(data$brix~data$var,)
stripchart(data$brix~data$var,
method = "jitter",
col = "blue",
vertical = TRUE,
pch = 19, add = TRUE)
Prueba de hipotesis H0:mu var1 = mu var2 Hi: mu var1 != mu var2
varianza de cada grupo (variedad)
tapply(data$brix, data$var, var)
## VR1 VR2
## 1.731974 2.325301
Prueba de igualdad de varianzas
Ho: var 1 = var 2 Ha: var 1 != var 2
var.test(data$brix~data$var) # No rechazo
##
## F test to compare two variances
##
## data: data$brix by data$var
## F = 0.74484, num df = 59, denom df = 59, p-value = 0.2608
## alternative hypothesis: true ratio of variances is not equal to 1
## 95 percent confidence interval:
## 0.4449103 1.2469582
## sample estimates:
## ratio of variances
## 0.7448386
# como el p valor de la prueba de varianza es mayor al 0.05 no se rechaza Ho de la prueba de varianzas
Prueba de medias H0: med var1 = med var2 H1: med var2 != med var2
tt_1 = t.test(data$brix~data$var,
alternative = 't',
paired = F,
var.equal = T)
tt_1
##
## Two Sample t-test
##
## data: data$brix by data$var
## t = -7.4058, df = 118, p-value = 2.119e-11
## alternative hypothesis: true difference in means between group VR1 and group VR2 is not equal to 0
## 95 percent confidence interval:
## -2.440759 -1.410856
## sample estimates:
## mean in group VR1 mean in group VR2
## 16.09341 18.01922
Comparar 2 Promedios pareados Cocción de Agave Contenido de azúcares antes y después de la cocción
set.seed(2025)
az_a=rnorm(120,8,0.5)
az_d=rnorm(120,7.7,0.4)
par(mfrow = c(1, 2))
boxplot(az_a, main = 'Contenido azucar antes',
ylim = c(6,10))
boxplot(az_d, main = 'Contenido azucar despues',
ylim = c(6,10))
Pueba de hipótesis por varianza entre tratamientos H0: mu az antes = mu
az después Hi: mu az antes != mu az después Pureba t para 2 muestras
pareadas
ttest_2 = t.test(az_a, az_d,
alternative = 'g',
paired = T)
ttest_2
##
## Paired t-test
##
## data: az_a and az_d
## t = 5.297, df = 119, p-value = 2.737e-07
## alternative hypothesis: true mean difference is greater than 0
## 95 percent confidence interval:
## 0.2001709 Inf
## sample estimates:
## mean difference
## 0.291353
#P-valor < 0.05 rechazo H0
#si hay merma en el contenido de azúcar, este sí disminuye después de la cocción
Prueba para 2 Proporciones diferentes
pp: Porcentaje de parasitismo d: Dosis H0: pp d menor = pp dmayor H1: pp
d menor != pp dmayor
set.seed(535) # establecen variables
huevos_q1 = rbinom(n = 80,
size = 12,
prob = 0.5)
pars_1 = round(huevos_q1**(1/3))
porc_par_1 = round(100*pars_1/huevos_q1, 2)
huevos_q2 = rbinom(n = 81,
size = 11,
prob = 0.6)
pars_2 = round(huevos_q2**(1/2))
porc_par_2 = round(100*pars_2/huevos_q2, 2)
hist(porc_par_2)
Histograma para la porción paracitada de huevos 2
hist(porc_par_1)
hist(porc_par_2)
Datos para la prueba
#Total parasitados de la dosis menor
x1 <- sum(pars_1)
#huevos totales, dosis menor
n1 = sum(huevos_q1)
# total parasitados de la dosis mayor
x2 = sum(pars_2)
# huevos totales dosis mayor
n2 = sum(huevos_q2)
n1
## [1] 480
n2
## [1] 546
Prueba
prop_test_2 = prop.test(x = c(x1, x2),
n = c(n1, n2),
alternative = "l")
prop_test_2
##
## 2-sample test for equality of proportions with continuity correction
##
## data: c(x1, x2) out of c(n1, n2)
## X-squared = 3.7842, df = 1, p-value = 0.02587
## alternative hypothesis: less
## 95 percent confidence interval:
## -1.00000000 -0.00920476
## sample estimates:
## prop 1 prop 2
## 0.3208333 0.3809524
#pvalor < 0.05 rechazo H0, dosis menor tiene menor parasitismo que dosis mayor