PreparED Study Materials
Videos
Americans on Marriage: Statistical Insights from a Sample
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Review a Pew Research Center study on Americans' beliefs about marriage. Through statistical analysis, understand the sampling distribution, standard deviation, and the probabilities surrounding various beliefs. The insights detail public sentiments and the significance of sample outcomes.
Confidence Intervals for Bag Weights: A Statistical Guide
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Understand the process of determining the 94.26% confidence interval for the median weight of "80-pound" bags of water softener pellets using a standard normal table and specified formulas. Additionally, explore the steps to deduce a confidence level of 90.47%.
Brand X vs. Brand Y: 95% Confidence in Voltage Difference
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Compare the voltages of Brand X and Brand Y batteries using statistical analysis. Learn how to determine a 95% confidence interval for their mean differences. Understand the process from data collection to interpretation of results.
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.
Testing the 123-Gallon Daily Water Claim: Fact or Fiction?
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Explore the claim that average daily water consumption is 123 gallons. Using statistical testing, we evaluate a new sample against the Old Farmer’s Almanac claim. Learn how to interpret p-values and t-scores in hypothesis testing.
Comparing Stock Returns & Volatility: T-test and F-test Insights
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Compare the mean returns and volatilities of two stocks using t-test and F-test methods. Through the application of hypothesis testing and P-value calculations, we determine which stock provides higher returns and which is riskier.



















