punto 1 parcial probabilidad y estadistica

data("mtcars")
df <- mtcars

con este comando summary lo que hacemos es que conocemos nuestro mínimo, 1er cuartil, mediana, media, 3er cuartil y máximo.

summary(df)

##       mpg             cyl             disp             hp       
##  Min.   :10.40   Min.   :4.000   Min.   : 71.1   Min.   : 52.0  
##  1st Qu.:15.43   1st Qu.:4.000   1st Qu.:120.8   1st Qu.: 96.5  
##  Median :19.20   Median :6.000   Median :196.3   Median :123.0  
##  Mean   :20.09   Mean   :6.188   Mean   :230.7   Mean   :146.7  
##  3rd Qu.:22.80   3rd Qu.:8.000   3rd Qu.:326.0   3rd Qu.:180.0  
##  Max.   :33.90   Max.   :8.000   Max.   :472.0   Max.   :335.0  
##       drat             wt             qsec             vs        
##  Min.   :2.760   Min.   :1.513   Min.   :14.50   Min.   :0.0000  
##  1st Qu.:3.080   1st Qu.:2.581   1st Qu.:16.89   1st Qu.:0.0000  
##  Median :3.695   Median :3.325   Median :17.71   Median :0.0000  
##  Mean   :3.597   Mean   :3.217   Mean   :17.85   Mean   :0.4375  
##  3rd Qu.:3.920   3rd Qu.:3.610   3rd Qu.:18.90   3rd Qu.:1.0000  
##  Max.   :4.930   Max.   :5.424   Max.   :22.90   Max.   :1.0000  
##        am              gear            carb      
##  Min.   :0.0000   Min.   :3.000   Min.   :1.000  
##  1st Qu.:0.0000   1st Qu.:3.000   1st Qu.:2.000  
##  Median :0.0000   Median :4.000   Median :2.000  
##  Mean   :0.4062   Mean   :3.688   Mean   :2.812  
##  3rd Qu.:1.0000   3rd Qu.:4.000   3rd Qu.:4.000  
##  Max.   :1.0000   Max.   :5.000   Max.   :8.000

library(psych)

## Warning: package 'psych' was built under R version 4.5.1

describe(df)

# Histograma de cada variable
par(mfrow = c(3, 4))  # Para mostrar varios gráficos en una sola ventana
for (var in names(df)) {
  hist(df[[var]], main = paste("Histograma de", var), xlab = var, col = "lightblue", border = "black")
}

# Boxplots
par(mfrow = c(3, 4))
for (var in names(df)) {
  boxplot(df[[var]], main = paste("Boxplot de", var), col = "orange", horizontal = TRUE)
}

pairs(df, main = "Matriz de dispersión de mtcars", pch = 21, bg = "lightgreen")

library(corrplot)

## Warning: package 'corrplot' was built under R version 4.5.1

## corrplot 0.95 loaded

cor_matrix <- cor(df)
corrplot(cor_matrix, method = "circle")

df$cyl <- as.factor(df$cyl)
df$gear <- as.factor(df$gear)
df$carb <- as.factor(df$carb)

# Gráficos de barras
library(ggplot2)

## 
## Adjuntando el paquete: 'ggplot2'

## The following objects are masked from 'package:psych':
## 
##     %+%, alpha

ggplot(df, aes(x = cyl)) + geom_bar(fill = "steelblue") + ggtitle("Número de cilindros")

# Gráfico de barras para 'gear' (número de marchas)
ggplot(df, aes(x = gear)) + 
  geom_bar(fill = "darkseagreen") + 
  ggtitle("Distribución del número de marchas")

# Gráfico de barras para 'carb' (número de carburadores)
ggplot(df, aes(x = carb)) + 
  geom_bar(fill = "mediumpurple") + 
  ggtitle("Distribución del número de carburadores")

ggplot(df, aes(x = cyl, y = mpg)) + 
  geom_boxplot(fill = "tomato") + 
  ggtitle("Rendimiento (mpg) según número de cilindros")