Question 1: Descriptive Statistics for Tribe Data
Problem Description:
Analyze the dataset 'tribe.RData' containing height and weight information.
- Mean height: 167.8419 cm
- Mean weight: 64.5607 kg
- Median height: 168.115 cm
- Standard deviation of height: 7.068682 cm
- Standard deviation of weight: 11.88245 kg
- Correlation between weight and height: 0.1949294
Question 2: Correlation Analysis of Midterm and Final Exam Grades
Problem Description:
Examine the dataset 'grades.csv' with information about midterm and final exam grades.
- Sample size: 73 students
- Correlation for all students: 0.6701399
- Correlation for a subset of 30 students: 0.2593948
- Explanation: The correlation in part (e) is smaller due to the reduction in sample size. With a larger sample, the correlation approaches the population correlation coefficient.
Question 3: Frequentist vs Bayesian Perspectives on Probability
Problem Description:
Discuss the differences between the frequentist and Bayesian perspectives on the definition of probability.
- Frequentists see probability as relative frequency: Bayesians view it as a function of belief.
- Frequentists rely on experiments: Bayesians use prior knowledge.
- Frequentists treat parameters as fixed: Bayesians treat them as random variables.
Question 4: Sample Space of an Experiment
Problem Description:
List all elements in the sample space of an experiment.
- Sample space: {HHH, HHT, HTH, THH, HTT, THT, TTH, TTT}
Question 5: Meal Combinations
Problem Description:
Calculate the number of meal combinations possible.
- Number of salads: 2
- Number of main dishes: 4
- Number of desserts: 3
- Number of meal combinations: 24
Question 6: Arrangement of Letters in a Word
Problem Description:
Calculate the ways the letters of the word "CATHY" can be arranged.
- Ways to arrange: 120
Question 7: Number of Different Committees
Problem Description:
Calculate the number of different committees possible.
- Number of committees: 1,140
Question 8: Committees with Women and Men
Problem Description:
Calculate the number of different committees consisting of 2 women and 3 men.
- Number of committees: 350
Question 9: Combinations Symmetry
Problem Description:
Explain why (n¦r) = (n¦(n-r)).
- Whenever r items are selected, n−r items are left over. Hence the number of combinations of n things taken r at a time is equal to the number of combinations of n things taken (n-r) at a time.
Question 10: Conditional Probability
Problem Description:
Calculate conditional probabilities for coin-flipping events.
- P(A│B): 1/2
- P(A│C): 1/3
Question 11: Probability of Correct Guessing
Problem Description:
Calculate the probability of correctly guessing four milk-first cups out of eight.
- Probability: 1 in 70 or 1.4%
Question 12: Coin Flipping Probability
Problem Description:
Calculate the probability of getting all heads when flipping four fair coins.
- Probability: 1/16