Lecture 6.2 - Scatter Plot, Correlation, & Lines of Fit

Multiple Choice

Which of the following best describes bivariate data?

• Data with two variables

• Data with one variable

• Data with three variables

• Data with no variables

Multiple Choice

What is the main purpose of a scatter plot?

• To show the relationship between two variables

• To display a single variable's distribution

• To compare means of two groups

• To show frequency of categories

Multiple Choice

Which types of correlation are shown in the diagrams, and how can you identify them?

• Positive, negative, and no correlation; identified by the direction of the slope and clustering of points

• Only positive correlation; identified by upward slope

• Only negative correlation; identified by downward slope

• No correlation; identified by random points

Multiple Choice

What type of correlation does this scatter plot show?

• positive linear association
• negative linear association
• no association
• nonlinear association

Multiple Choice

What type of correlation does this graph have?

• positive
• negative
• none
• all of the above

Multiple Choice

• A

• B

• C

• D

Multiple Choice

• A

• B

• C

• D

Multiple Select

Select all statements that are true about causation.

• Causation means one variable directly affects another

• Causation always implies correlation

• Correlation always implies causation

• Causation can be identified by controlled experiments

Open Ended

Explain the difference between correlation and causation using examples from the lesson.

Multiple Choice

Which example shows CAUSATION? (Which one CAUSED the other to happen.)

• High social media usage and reduced grades.

• Car ran out of gas and being stranded on the side of the road.

• Recess time and number of friends.

Multiple Choice

Which example shows CAUSATION? (Which one CAUSED the other to happen.)

• Rainfall and time spent reading.

• Eating more butter and increased divorce rates.

• It started raining and the baseball game was delayed.

Multiple Choice

Which example shows CORRELATION? (The events show correlation, but one thing does NOT cause the other thing to happen.)

• I put water in the freezer and now I have ice.

• The alarm clock went off and I woke up.

• Temperature and the amount of people at the beach.

Multiple Choice

Which example shows a CORRELATION? (The events show correlation, but one thing does NOT cause the other thing to happen.)

• It rained and the ground is wet.

• Ice cream sales increase as temperature increases.

Open Ended

Determine whether the graph shows a positive, negative, or no correlation. If there is a positive or negative correlation, describe its meaning in the situation.

Multiple Choice

Which of the following best describes a line of fit (trend line) in a scatter plot?

• A line that describes the trend of the data

• A line that connects all the points exactly

• A line that is always horizontal

• A line that is always vertical

Multiple Choice

Based on the sales data for fast food restaurants from 2004 to 2012, what type of relationship exists between year and sales?

• Positive correlation

• Negative correlation

• No correlation

• Cyclical correlation

Multiple Choice

What is linear extrapolation used for?

• To predict values outside the data set

• To predict values inside the data set

• To describe the trend of the data

• To connect all data points

For a line of fit, you may pick any two points to represent the data and write an equation to represent the data.

Open Ended

Identify the independent and dependent variables in the zebra mussel population growth data. Is there a relationship in the data? If so, predict the number of zebra mussels in 2039.

Multiple Choice

Based on the equation y = 65x - 5, what is the predicted value for y when x = 3?

• 190

• 200

• 180

• 195