Statistical Analysis Quiz No 2

What does a higher standard deviation signify?

• More variability in the data

• Less variability in the data

• No variability in the data

• No conclusion can be drawn

In linear regression, what does the coefficient of determination (R-squared) measure?

• The strength of the relationship between independent and dependent variables

• The slope of the regression line

• The residual error in the model

• The correlation between independent and dependent variables

If all values in a dataset are identical, what is the standard deviation?

• Zero

• One

• Indeterminate

• Cannot be calculated

In linear regression, what is the purpose of the intercept term?

• It represents the change in the dependent variable for a unit change in the independent variable.

• It shifts the regression line up or down on the y-axis.

• It signifies the correlation between variables.

• It is not necessary in linear regression.

Which component of time series represents irregular fluctuations and unpredictable events?

• Trend

• Seasonality

• Cyclical fluctuations

• Residuals

In a normal distribution, what percentage of data points fall within one standard deviation from the mean?

• 25%

• 50%

• 68%

• 95%

If a dataset has outliers, how does this affect the standard deviation?

• Standard deviation increases

• Standard deviation decreases

• Standard deviation remains unchanged

• Cannot be determined without knowing the values of the outliers

Which measure of dispersion is sensitive to outliers?

• Variance

• Median

• Range

• Interquartile Range

What does the slope of the regression line represent?

• The change in the independent variable for a unit change in the dependent variable.

• The change in the dependent variable for a unit change in the independent variable.

• The correlation between variables.

• The intercept of the regression line.

What does the standard deviation measure in a dataset?

• Central tendency

• Spread or variability

• The highest value

• The lowest value