Discrete Random Variables

# Discrete Distribution (Playing Card Experiment)

OpenStaxCollege

[latexpage]

Class Time:

Names:

- The student will compare empirical data and a theoretical distribution to determine if an everyday experiment fits a discrete distribution.
- The student will demonstrate an understanding of long-term probabilities.

- One full deck of playing cards

ProcedureThe experimental procedure is to pick one card from a deck of shuffled cards.

- The theoretical probability of picking a diamond from a deck is _________.
- Shuffle a deck of cards.
- Pick one card from it.
- Record whether it was a diamond or not a diamond.
- Put the card back and reshuffle.
- Do this a total of ten times.
- Record the number of diamonds picked.
- Let
*X*= number of diamonds. Theoretically,*X*~*B*(_____,_____)

- Record the number of diamonds picked for your class in [link]. Then calculate the relative frequency.

*x*Frequency Relative Frequency 0 __________ __________ 1 __________ __________ 2 __________ __________ 3 __________ __________ 4 __________ __________ 5 __________ __________ 6 __________ __________ 7 __________ __________ 8 __________ __________ 9 __________ __________ 10 __________ __________ - Calculate the following:
- \(\overline{x}\) = ________
*s*= ________

- Construct a histogram of the empirical data.

- Build the theoretical PDF chart based on the distribution in the Procedure section.

*x**P*(*x*)0 1 2 3 4 5 6 7 8 9 10 - Calculate the following:
*μ*= ____________*σ*= ____________

- Construct a histogram of the theoretical distribution.

Using the Data

*RF* = relative frequency

Use the table from the Theoretical Distribution section to calculate the following answers. Round your answers to four decimal places.

*P*(*x*= 3) = _______________________*P*(1 <*x*< 4) = _______________________*P*(*x*≥ 8) = _______________________

Use the data from the Organize the Data section to calculate the following answers. Round your answers to four decimal places.

*RF*(

*x*= 3) = _______________________

*RF*(1 <

*x*< 4) = _______________________

*RF*(

*x*≥ 8) = _______________________

Discussion QuestionsFor questions 1 and 2, think about the shapes of the two graphs, the probabilities, the relative frequencies, the means, and the standard deviations.

- Knowing that data vary, describe three similarities between the graphs and distributions of the theoretical and empirical distributions. Use complete sentences.
- Describe the three most significant differences between the graphs or distributions of the theoretical and empirical distributions.
- Using your answers from questions 1 and 2, does it appear that the data fit the theoretical distribution? In complete sentences, explain why or why not.
- Suppose that the experiment had been repeated 500 times. Would you expect [link] or [link] to change, and how would it change? Why? Why wouldn’t the other table change?