Essentials of Statistics for Business and Economics, Chapter 14 - Simple Regression Exam Questions with

Essentials of Statistics for Business and Economics, Chapter 14 - Simple Regression Exam Questions with Answers What is regression analysis? - Correct Answers: This is a widely used procedure to relate an outcome, or dependent, variable (denoted y) to one or more independent, or predictor, variables (denoted x1, x2, etc.). What is a dependent variable? - Correct Answers: This is the variable that is measured, and is denoted y. What is the independent variable? - Correct Answers: This is the variable that changed, and is denoted x. What is simple linear regression? - Correct Answers: This always involves one independent variable and one dependent variable. The relationship between the two variables is denoted by a straight line. In statistics, simple linear regression. In other words, it fits a straight line through the set of n points in such a way that makes the sum of squared residuals of the model (that is, vertical distances between the points of the data set and the fitted line) as small as possible. What is the simple linear regression model? - Correct Answers: This describes how y is related to x and an error term. The model is as follows: What is the simple linear regression equation? - Correct Answers: The equation is as follows: What is an error term? - Correct Answers: This is a variable in a statistical or mathematical model, which is created when the model does not fully represent the actual relationship between the independent variables and the dependent variables. As a result of this incomplete relationship, the error term is the amount at which the equation may differ during empirical analysis. What is a positive linear relationship? - Correct Answers: This is when the slope of β1 is positive and slopes up. What is a negative linear relationship? - Correct Answers: This is when the slope of β1 is negative and slopes down. What does the slope of a simple regression look like when there is no relationship? - Correct Answers: In this situation, the line is perfectly horizontal. What is the estimated simple linear regression equation? - Correct Answers: The equation is as follows: What is the coefficient of determination? - Correct Answers: In a simple linear regression with only one independent variable, this is the square of the coefficient of correlation. It is represented by the term r2. The equation is as follows: What is a t-value? - Correct Answers: This measures the size of the difference relative to the variation in your sample data. Put another way, it is simply the calculated difference represented in units of standard error, AKA, it equals the coefficient divided by the standard error. The great this value (it can be either positive or negative), the greater the evidence against the null hypothesis that there is no significant difference. The closer it is to 0, the more likely there isn't a significant difference. What is the Confidence Interval for the mean of y? - Correct Answers: This is calculated as: How do you calculate the confidence interval for E(yp)? - Correct Answers: This is calculated as follows: