Assignment #2

180 points

Author

Esteban Montenegro-Montenegro

Published

June 16, 2025

Description

In this second assignment, you’ll have to solve several applied tasks. You’ll have the chance to solve applied data analysis tasks using R, or Jamovi.

What happens if you don’t understand how to answer an exercise ?

In this assigment I will provide videos on how to solve the exercises, or I’ll explain the solution in class. If after the explanation, you still have questions don’t hesitate to send me an email.

Part 1: Review important concepts

In this section, you will see TRUE/FALSE questions, or multiple choice questions. Select only one option. (10 points each correct answer).

Please copy the question along with your answer in a Word document.

  1. A \(t\)-test may be used when my dependent variable is continuous and the independent variable is a nominal variable with only two levels:


  1. The options to label A and B are: (check the module "Data Visualizations on Canvas")



  1. The above figure is a QQ-plot, can you conclude that Life Expectancy in Costa Rica comes from a normally distributed process? (check the module "Data Visualizations on Canvas")


  1. The above figure represents a:




  1. In the Classical Regression Model, the estimated slope of the regression is often represented with the Greek letter \(\beta\) (beta). Taking this into consideration, if my estimated \(\beta\) is equals to a value greater than \(0\), I can conclude that there is a positive relationship between my outcome and my predictor:


  1. The Classical Regression Model does not have any distributional assumption on the predictors


  1. The Classical Regression Model assumes that the dependent variable or outcome must come from a normal distribution:


  1. The following model represents:
\[\begin{equation} Y = \beta_{0}+ \beta_{1}X_{1} + \beta_{2}X_{2} + \epsilon \end{equation}\]



  1. One of the assumptions of ANOVA is constant variance in all groups:


  1. Pedro performed an experiment aiming to delay dementia symptoms in older adults. In this study, Pedro created three random conditions: A) A group attending yoga class, B) A group attending weight lifting, and finally, C) A group attending nutrition classes. Pedro measured the working memory capacity at the end of the study as a dependent variable. The problem for Pedro is that he doesn’t know which statistical model he should estimate.

What model should Pedro estimate on his data to test the mean differences between groups?