Scatterplots-Correlation & Best Fit Lines

Front

What is a scatterplot?

Back

A scatterplot is a graph that shows the relationship between two quantitative variables by displaying data points on a two-dimensional axis.

Front

What does a trend line represent in a scatterplot?

Back

A trend line, or line of best fit, represents the general direction that a group of points seem to be heading, helping to predict values.

Front

How do you determine the line of best fit?

Back

The line of best fit is determined by minimizing the distance between the line and all the data points, often using the least squares method.

Front

What is correlation in the context of scatterplots?

Back

Correlation refers to the strength and direction of a relationship between two variables, which can be positive, negative, or no correlation.

Front

What does a positive correlation look like on a scatterplot?

Back

A positive correlation appears as an upward slope, where as one variable increases, the other variable also increases.

Front

What does a negative correlation look like on a scatterplot?

Back

A negative correlation appears as a downward slope, where as one variable increases, the other variable decreases.

Front

What is no correlation?

Back

No correlation means there is no discernible relationship between the two variables, and the points on the scatterplot are scattered randomly.

Front

What is the purpose of using a trend line to make predictions?

Back

A trend line helps to estimate the value of one variable based on the value of another variable, providing a visual representation of the relationship.

Front

How can you use a scatterplot to predict values?

Back

You can use the trend line to find the corresponding value of one variable when you know the value of the other variable.

Front

What is the formula for the slope of a line?

Back

The slope (m) of a line is calculated as m = (y2 - y1) / (x2 - x1), where (x1, y1) and (x2, y2) are two points on the line.