Flashcard on Statistical Concepts

Front

What is the least-squares regression?

Back

A statistical method used to determine the line of best fit for a set of data points, minimizing the sum of the squares of the vertical distances of the points from the line.

Front

What does a correlation coefficient (r) indicate?

Back

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

Front

What is the purpose of a histogram?

Back

To visualize the distribution of a single quantitative variable by showing the frequency of data points within specified ranges.

Front

What does a correlation of 0 mean?

Back

It indicates that there is no linear association between the two variables being analyzed.

Front

What happens to the predicted value in a regression equation when the independent variable increases by 1 unit?

Back

The predicted value increases or decreases by the coefficient of that independent variable.

Front

What is the range of values for the correlation coefficient (r)?

Back

-1 ≤ r ≤ 1.

Front

How does changing the scale of measurement affect the correlation coefficient?

Back

The correlation coefficient remains unchanged regardless of whether the data is expressed in raw scores or percentages.

Front

What is the difference between correlation and causation?

Back

Correlation indicates a relationship between two variables, while causation implies that one variable directly affects the other.

Front

What is a scatterplot?

Back

A graphical representation of two quantitative variables, showing the relationship between them using points on a Cartesian plane.

Front

What does it mean if a scatterplot shows a positive correlation?

Back

As one variable increases, the other variable also tends to increase.