Scatterplots

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 a positive correlation in a scatterplot indicate?

Back

A positive correlation indicates that as one variable increases, the other variable also tends to increase.

Front

What does a negative correlation in a scatterplot indicate?

Back

A negative correlation indicates that as one variable increases, the other variable tends to decrease.

Front

What does no correlation mean in a scatterplot?

Back

No correlation means there is no apparent relationship between the two variables; changes in one variable do not predict changes in the other.

Front

How can you identify a linear relationship in a scatterplot?

Back

A linear relationship can be identified if the points in the scatterplot form a straight line or a pattern that closely resembles a straight line.

Front

What is the purpose of using scatterplots?

Back

Scatterplots are used to visually assess the relationship between two quantitative variables.

Front

What does the slope of a line in a scatterplot represent?

Back

The slope represents the rate of change between the two variables; a steeper slope indicates a stronger relationship.

Front

How do you interpret the distance between points in a scatterplot?

Back

The distance between points indicates the variability of the data; closer points suggest a stronger relationship, while widely spaced points suggest a weaker relationship.

Front

What is the significance of outliers in a scatterplot?

Back

Outliers are points that fall far from the general pattern of the data and can significantly affect the correlation and interpretation of the relationship.

Front

What is the formula for calculating correlation coefficient (r)?

Back

The correlation coefficient (r) is calculated using the formula: r = (nΣxy - ΣxΣy) / √[(nΣx² - (Σx)²)(nΣy² - (Σy)²)], where n is the number of pairs.