Gathering Data (C11-13 BVD)

C11: Understanding Randomness/Simulations

*AP Statistics Review

*Random

*An event is random if we know what outcomes could happen, but not which particular values did or will happen.

*Generating truly random numbers is hard. See random.org for details. Most calculators/computers generate pseudorandom numbers. They mimic random behavior, but if you knew the algorithm generating them, you would know what particular number would come next.

*Generating Pseudorandom

Numbers on TI-84

*Math key – PRB menu

*TI-nspire: Menu – Probability-Number-Random

*Simulations of Random Events: 7

Steps

*1. Identify component to be repeated in multiple trials of generating random numbers.

*2.Explain how you will use randomly generated digits to model the outcome of a trial.

*3. Explain how you will simulate one complete trial by generating the random numbers.

*4. Clearly state what you will be counting – i.e. identify your response variable.

*Simulations of Random Events: 7

Steps

*5. Run several trials. (More is better).

*6. Analyze the outcomes of your several trials – usually this means find the average.

*7. State your conclusion. Use your result from step 6 to write a sentence that explains the meaning or implication of the result in context.

*Example: page 224 #13

*You are about to take the road test for your driver’s license. You hear that only 34% of candidates pass the test the first time, but the percentage rises to 74% on retests. Estimate the average number of tests drivers take to get a license using a simulation.

*1. Identify component to be repeated in multiple

trials of generating random numbers.

*2.Explain how you will use randomly generated

digits to model the outcome of a trial.

*3. Explain how you will simulate one complete trial by generating the

random numbers.

*4. Clearly state what you will be counting – i.e.

identify your response

variable.

*5. Run several trials. (More is

better).

*6. Analyze the outcomes of your

several trials – usually this means find the

average.

*7. State your conclusion