Describing Variability

This target depicts

• High bias, high variability

• High bias, low variability

• Low bias, low variability

• Low bias, high variability

This target depicts what?

• Low bias, low variability

• High bias, low variability

• Low bias, high variability

• High bias, high variability

Which word refers to how spread out the data is?

• Variability

• Mean

• Median

• Mode

Which dot plot shows a GREATER VARIABILITY?

• Team 1 (top)

• Team 2 (bottom)

• They have the same variability

Choose the most appropriate measure to describe variation.

• MAD

• IQR

You may want to know what the average starting salary is for a graduate with a Bachelor’s degree. You could ask 1000 recently graduated students from a nearby university what their starting salary is and find the average, or you could just ask your brother who recently graduated what his salary is.

Instead of your brother, you ask one other random graduate their starting salary. Would you expect their salary to be close to your brother’s salary? Why or why not?

• Yes, because all graduates have similar starting salaries.

• No, because starting salaries can vary widely among graduates.

• Yes, if they are in the same field and location.

• No, unless they have negotiated the same terms.

• Yes, you get what you get and don't get upset

Match the following

• It is every member of the group we are studying or analyzing

• Standard Deviation

• It is a word that describes how widely spread our data is

• Sample

• The average distance of a data point to the mean

• Variability

• It is a value that falls significantly far away from the majority of our data

• Outlier

• It is a smaller group that we study to predict how the entire group will respond

• Population

What does VARIABILITY mean?

• How spread out the data is

• Variables, like x and y

• Varies & Changes

Which box plot shows a GREATER VARIABILITY?

• Afternoon (top)

• Morning (bottom)

• They have the same variability

Which box plot shows a GREATER VARIABILITY?

• Ramy (top)

• Mona (bottom)

• They have the same variability