Statistical Analysis Flashcard

Front

What does the slope of a regression line represent?

Back

The slope indicates the predicted change in the dependent variable for each one-unit increase in the independent variable.

Front

What is correlation in statistics?

Back

Correlation measures the strength and direction of a linear relationship between two variables, ranging from -1 to 1.

Front

What does a correlation coefficient (r) of 0.7 indicate?

Back

It indicates a strong positive correlation between the two variables.

Front

What is a residual in a regression analysis?

Back

A residual is the difference between the observed value and the predicted value from a regression model.

Front

What does it mean if a data point has a positive residual?

Back

It means the observed value is higher than the predicted value.

Front

How does adding an outlier affect correlation?

Back

Correlation is resistant to outliers, so it may stay nearly the same.

Front

What happens to correlation when changing units of measurement?

Back

The correlation coefficient (r) does not change when the units of measurement are changed.

Front

What is the purpose of a scatterplot?

Back

A scatterplot visually represents the relationship between two quantitative variables.

Front

What does a correlation coefficient of -0.49 indicate?

Back

It indicates a moderate negative correlation between the two variables.

Front

What is the interpretation of a correlation coefficient of 1?

Back

It indicates a perfect positive linear relationship between the two variables.