In simple linear regression, what does the slope of the regression line represent?
The point where the regression line crosses the y-axis
The change in the dependent variable for a one-unit change in the independent variable
The average value of the dependent variable
The strength of the relationship between the variables
What does an R-squared value of 0.80 indicate?
The slope of the regression line is 0.80.
20% of the variation in the dependent variable is explained by the independent variable.
80% of the variation in the dependent variable is explained by the independent variable.
The correlation between the variables is 0.80.
You're playing a game where you flip a coin. Heads, you win $10. Tails, you lose $5. What is the expected value of playing this game?
$0.00
-$2.50
$5.00
$2.50
A Chi-square test is most appropriate for analyzing which type of data?
Continuous data
Categorical data
Normally distributed data
Time series data
A normal distribution has a mean of 50 and a standard deviation of 10. What is the probability that a randomly selected value from this distribution is between 40 and 60?
0.3413
0.9545
0.9973
0.6827
The number of cars passing a certain point on a highway averages 10 per hour. What is the probability that exactly 15 cars pass that point in a given hour?
0.5
0.0347
0.15
0.25
In factor analysis, what does the term 'communality' refer to?
The uniqueness of a particular variable
The correlation between two factors
The eigenvalue of a factor
The proportion of variance in a variable explained by all factors
When is ANOVA (Analysis of Variance) used instead of a t-test?
When comparing the variances of two groups.
When analyzing the relationship between two categorical variables.
When comparing the means of two groups.
When comparing the means of three or more groups.
In multiple regression, what does a high variance inflation factor (VIF) indicate?
Heteroscedasticity in the residuals
A good fit of the regression model
High multicollinearity among predictor variables
Low multicollinearity among predictor variables
What is the primary purpose of inferential statistics?
To organize and clean raw data.
To visually represent data using graphs and charts.
To describe and summarize data.
To make generalizations about a population based on a sample.