Scatterplots and Linear Regression

Front

What is a scatterplot?

Back

A scatterplot is a graph that displays values for typically two variables for a set of data. Each point represents an observation in the dataset.

Front

What does correlation mean in statistics?

Back

Correlation refers to a statistical measure that describes the extent to which two variables change together. It can be positive, negative, or zero.

Front

What is a strong positive correlation?

Back

A strong positive correlation means that as one variable increases, the other variable also increases, and the points on the scatterplot are closely clustered along a line.

Front

What is a weak negative correlation?

Back

A weak negative correlation indicates that as one variable increases, the other variable tends to decrease, but the relationship is not strong.

Front

What does the correlation coefficient (r) represent?

Back

The correlation coefficient (r) quantifies the strength and direction of a linear relationship between two variables, ranging from -1 to 1.

Front

What is the line of best fit?

Back

The line of best fit is a straight line that best represents the data on a scatterplot, minimizing the distance between the line and all data points.

Front

How do you interpret a correlation coefficient of r = 0?

Back

A correlation coefficient of r = 0 indicates no correlation between the two variables; changes in one variable do not predict changes in the other.

Front

What is the formula for a linear equation in slope-intercept form?

Back

The formula is y = mx + b, where m is the slope and b is the y-intercept.

Front

What does a positive slope indicate in a linear regression?

Back

A positive slope indicates that as the independent variable increases, the dependent variable also increases.

Front

How can you use a scatterplot to make predictions?

Back

You can use a scatterplot to make predictions by identifying the trend in the data and using the line of best fit to estimate values.