Galton <- read_csv("Galton.csv")
## Rows: 898 Columns: 6
## ── Column specification ────────────────────────────────────────────────────────
## Delimiter: ","
## chr (2): FamilyID, Gender
## dbl (4): FatherHeight, MotherHeight, Height, NumKids
## 
## ℹ Use `spec()` to retrieve the full column specification for this data.
## ℹ Specify the column types or set `show_col_types = FALSE` to quiet this message.
head(Galton)
## # A tibble: 6 Ă— 6
##   FamilyID FatherHeight MotherHeight Gender Height NumKids
##   <chr>           <dbl>        <dbl> <chr>   <dbl>   <dbl>
## 1 1                78.5         67   M        73.2       4
## 2 1                78.5         67   F        69.2       4
## 3 1                78.5         67   F        69         4
## 4 1                78.5         67   F        69         4
## 5 2                75.5         66.5 M        73.5       4
## 6 2                75.5         66.5 M        72.5       4
ggpairs(Galton, columns = c(2, 3, 5))

modelo.fit <- lm(Height ~ FatherHeight, data = Galton)
summary(modelo.fit)
## 
## Call:
## lm(formula = Height ~ FatherHeight, data = Galton)
## 
## Residuals:
##      Min       1Q   Median       3Q      Max 
## -10.2683  -2.6689  -0.2092   2.6342  11.9329 
## 
## Coefficients:
##              Estimate Std. Error t value Pr(>|t|)    
## (Intercept)  39.11039    3.22706  12.120   <2e-16 ***
## FatherHeight  0.39938    0.04658   8.574   <2e-16 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 3.446 on 896 degrees of freedom
## Multiple R-squared:  0.07582,    Adjusted R-squared:  0.07479 
## F-statistic: 73.51 on 1 and 896 DF,  p-value: < 2.2e-16
coef(modelo.fit)
##  (Intercept) FatherHeight 
##   39.1103868    0.3993813
head(modelo.fit$residuals,10)
##         1         2         3         4         5         6         7         8 
##  2.738184 -1.261816 -1.461816 -1.461816  4.236328  3.236328 -3.763672 -3.763672 
##         9        10 
##  1.936018 -1.063982
ggplot(Galton , aes(x = FatherHeight, y = Height)) +
  geom_point(color = "red") +
  theme_minimal()

ggplot(Galton, aes(x = FatherHeight, y = Height)) + 
  geom_point(color = "red") +
  geom_smooth(method = "lm", formula = y ~ x, se = FALSE, col = "blue") +
  theme_light()