set.seed(1989,sample.kind = "Rounding")
library(HistData)
library(dplyr)
data("GaltonFamilies")

female_heights<-GaltonFamilies%>%
  filter(gender=="female")%>%
  group_by(family)%>%
  sample_n(1)%>%ungroup()%>%
  select(mother,childHeight)%>%
  rename(daughter=childHeight)

#mother height mean
mean(female_heights$mother)
#64.125

#mother height std dev
sd(female_heights$mother)
#2.289292

#daughter height mean
mean(female_heights$daughter)
#64.28011

#daughter height std dev
sd(female_heights$daughter)
#2.39416

#Correlation coeff
cor(female_heights$mother,female_heights$daughter)
#0.3245199


#Question 9
#slope of regression line predicting daughters height from mothers height
model_9a<-lm(daughter~mother, data=female_heights)  
print(model_9a)
#0.3394

#intercept of regression line predicting daughters height from mothers height
print(model_9a)
#42.5170

#Change in daughters height given 1 inch change in mothers height
print(model_9a)
#0.3394