PreparED Study Materials
STAT 243: Statistics 243
School: Portland State University
Number of Notes and Study Guides Available: 2
Notes
Videos
Real Cowboys' Lifespan: Debunking Wild West Myths
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Explore the actual longevity of legendary cowboys using a detailed sociological study. With data visualization and historical references, challenge popular stereotypes and understand the reality of cowboy lives in the late 19th century.
Pet Phone Calls: Validating a 37% Claim with Z-test
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Explore a claim from the American Animal Hospital Association that 37% of pet owners communicate with their pets over the phone. Through hypothesis testing and a z-test, evaluate a skeptical veterinarian's doubts. Conclusions shed light on pet owners' unique communication habits.
Eye Color & Assortative Mating in Scandinavian Couples
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Explore the concept of assortative mating through an eye-color study of 204 Scandinavian couples. Discover how probabilities highlight nonrandom mating patterns. Conclude if eye colors of partners are independent or reveal assortative tendencies.
Chi-Square Observations: Probability of Exceeding 7.779
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Discover how to compute the likelihood of observations exceeding a certain value in a chi-square distribution with 4 degrees of freedom. Using the binomial distribution formula, evaluate the chances of at most 3 out of 15 observations surpassing the 7.779 mark. Results highlight the intricacies of data distributions.
Understanding Mutually Exclusive Events: Real-life Scenarios
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Explore the concept of mutually exclusive events in probability, using practical examples like rolling a die, selecting college students, and understanding political party registrations.
Poisson Distribution in Event Count & Uranium Discovery
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Explore the dynamics of Poisson distribution using both theoretical understanding and a practical application related to discovering uranium deposits. With the help of Bayes' formula and parameter adjustments, interpret various probabilities and outcomes for event occurrences.

















