PreparED Study Materials
STAT 431: STAT 431
School: University of Pennsylvania
Number of Notes and Study Guides Available: 227
Notes
Study Guides
Videos
Analyzing Salad Habits: A Statistical Look at 85.5%
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Examine a survey of 200 adults regarding salad consumption, leading to a sample proportion of 85.5%. Using hypothesis testing and z-test calculations, the video determines whether more than 85% of American adults eat salad weekly. The results offer statistical insights into dietary habits.
2010 US Gas Prices: Insights with Chebyshev’s Inequality
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Unpack the average US gasoline prices in December 2010 using Chebyshev’s Inequality. Discover the minimum percentage of gas stations within specific price deviations. Learn how prices ranged based on standard deviations from the mean.
Analyzing Teen Texting: Confidence Interval & Plausibility
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Discover how to calculate the 95% confidence interval for a population proportion using sample data. Through a practical example about texting habits among American teens, learn the implications of this statistical tool and how to assess plausibility.
Analyzing Movie Habits Survey: Uncovering Hidden Biases
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Unpack the potential biases in a survey about movie-watching habits based on its design and constraints. Learn how limiting to residential phones and specific time frames can affect results. Recommendations are made to ensure a broader, more accurate perspective.
ACT Score Bet: Who Owes the Pizza? A 7.6% Chance Explained
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Discover the friendly bet between Leona and Fred surrounding their ACT scores and who owes who a pizza. Using statistical principles like Z-scores and the normal distribution, we'll decipher the odds of one outperforming the other by 5 points.
Let Y be a random variable with mean 11 and variance 9
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