A Chi-square test is most appropriate for analyzing which type of data?
Time series data
Normally distributed data
Categorical data
Continuous data
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.
What does a Pearson correlation coefficient of -0.9 suggest about the relationship between two variables?
Weak positive linear relationship
No linear relationship
Strong negative linear relationship
Strong positive linear relationship
Which of the following is NOT an assumption of linear regression?
Independence of observations
Normality of the independent variable
Linearity of the relationship between independent and dependent variables
Homoscedasticity (equal variance of errors)
Which component of a time series reflects long-term changes in the data over time?
Cyclical Variation
Irregularity
Trend
Seasonality
If the variance of a random variable is 9, what is its standard deviation?
3
81
18
9
An event has three possible outcomes: A, B, and C. You know P(A) = 0.2 and P(B) = 0.3. What is the value of P(C) according to the law of total probability?
0.5
0.7
0.3
Cannot be determined
In simple linear regression, what does the slope of the regression line represent?
The point where the regression line crosses the y-axis
The average value of the dependent variable
The change in the dependent variable for a one-unit change in the independent variable
The strength of the relationship between the variables
In factor analysis, what does the term 'communality' refer to?
The uniqueness of a particular variable
The proportion of variance in a variable explained by all factors
The correlation between two factors
The eigenvalue of a factor
A random variable X has the following probability distribution: P(X=0) = 0.2, P(X=1) = 0.3, P(X=2) = 0.5. What is the expected value of X?
1.2
1.5
1