Statistical Analysis and Experimental Design

Darren Starnes guides AP Statistics students through free response questions focusing on exploring and collecting data. The session covers describing data distributions using histograms, constructing box plots, and comparing data distributions. It also discusses identifying experimental units, treatments, and response variables, and methods for random assignment in experiments. The session concludes with a summary and a preview of the next session on probability.

What is the main focus of this session?

• Free response questions on exploring and collecting data

• Multiple choice questions

• Probability questions

• Graph interpretation

Which of the following is NOT a characteristic to describe a distribution?

• Variability

• Color

• Shape

• Center

What is the shape of the distribution for dissolved oxygen concentration in colder streams?

• Symmetrical

• Bimodal and skewed right

• Uniform

• Unimodal and skewed left

When constructing a box plot, which of the following is NOT typically indicated?

• Outliers

• Third quartile

• Median

• First quartile

What is the median dissolved oxygen concentration for warmer streams?

• 6.12 mg/L

• 4.39 mg/L

• 5.43 mg/L

• 11-12 mg/L

In the randomized experiment, what is the response variable?

• Presence of fibers

• Severity of cracks

• Type of concrete

• Number of driveways

How many driveways were used in the experiment?

• 120

• 90

• 60

• 30

What is the purpose of random assignment in an experiment?

• To ensure equal sample sizes

• To increase variability

• To reduce the number of variables

• To establish a cause and effect relationship

Which method can be used to randomly assign treatments in the experiment?

• Choosing the first 30 driveways

• Assigning based on driveway size

• Using alphabetical order

• Using a random number generator

What is the benefit of having a statistically significant result in an experiment?

• It eliminates all variability

• It confirms the hypothesis

• It allows for a cause and effect conclusion

• It reduces the sample size