IGCSE Scatter Diagrams and Correlation

What is a scatter diagram used for?

• To show the relationship between two variables

• To display data in categories

• To compare fractions

• To calculate the average of a dataset

What does each point on a scatter diagram represent?

• A single variable

• A pair of related values

• A frequency count

• A trend line

What is another term for a scatter diagram?

• Line graph

• Histogram

• Scatter plot

• Bar chart

A scatter plot with points increasing from left to right shows a:

• Negative correlation

• No correlation

• Positive correlation

• Undefined correlation

A scatter plot where points are randomly scattered suggests:

• A strong correlation

• No correlation

• A perfect correlation

• A linear trend

Which of the following represents a negative correlation?

• Number of study hours and exam scores

• Speed of a car and time taken to travel a fixed distance

• Number of pets and height of a person

• Age of a tree and its height

If the points on a scatter diagram form a perfect straight line, the correlation is:

• Strong

• Weak

• Perfect

• Moderate

If most points are close to the trend line, the correlation is:

• Weak

• Moderate

• Strong

• Zero

If the correlation between two variables is -0.85, what can be said about their relationship?

• Strong negative correlation

• Weak negative correlation

• No correlation

• Positive correlation

Which of the following is an example of a weak positive correlation?

• Height and shoe size

• Number of hours studied and test scores

• Temperature and amount of ice cream sold

• Weight and number of books read