Session 5 Quiz

What is variability?

• A mistake in data
• The natural differences and spread in data values
• A type of graph
• Data that is wrong

What is the range of the dataset 12, 45, 23, 8, 31?

• 45
• 37
• 8
• 23.8

What is the difference between signal and noise in data?

• They are the same thing
• Signal is a real pattern; noise is random variation with no meaning
• Signal is louder; noise is quieter
• Noise is more important

Your daily step count varies from 5,000 to 8,000. One day you walk 7,500. Is this unusual?

• Very unusual
• No — it is within your normal range
• Slightly unusual
• Impossible to tell

Why is a single unusual measurement usually not meaningful?

• Because measurements are always wrong
• Because random variation can produce extreme values by chance
• Because single measurements do not count
• Because you need a computer

What does a small range tell you?

• The data is wrong
• The data values are close together — the group is consistent
• There is not enough data
• The range is broken

How can understanding variability reduce stress?

• It cannot
• By knowing that natural fluctuation is normal, you avoid overreacting to single bad days
• By making everything the same
• By ignoring all data

When should you investigate a change in data?

• Never — all changes are random
• When the value falls outside the typical range or unusual values appear repeatedly
• Only when the change is very large
• Only when a teacher tells you to