1.4 Discussion Questions

Be prepared to answer the following questions. It is okay (even good!) to use R to discover the answers to these questions.

  1. What is the class of happiness? Why does it make sense to store data using objects of this class?
  2. What is the class of happiness$shs_tot?
  3. Why is the $ needed to reference columns in a data.frame?
  4. What is the output of happiness$shs_tot + 2?
  5. What class is the object produced by executing: c(happiness$shs_tot, happiness$group)?
  6. What is the difference between 1 and "1" in R?
  7. Why does Happiness$shs_tot + 2 return an error?