PreparED Study Materials
STAT 401: Statistical Methods for Research Workers
School: Iowa State University
Number of Notes and Study Guides Available: 4
Notes
Videos
Understanding Null vs Alternative Hypotheses in Real-world Scenarios
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Explore various scenarios and understand the fundamental principles of the null and alternative hypotheses in statistical testing. This video breaks down how these hypotheses represent current beliefs and potential deviations, aiding in the interpretation of statistical findings.
Job Trends Analysis: Normal Approximation & Z-Values
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Explore the nuances of determining the likelihood of specific employment patterns using statistical methods. Understand the application of the normal approximation to the binomial distribution and the role of z-values in probability determinations. Gain clarity on interpreting employment trends with the help of a standard normal table.
Analyzing Age Distribution of Proofreaders: A Statistical Approach
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Discover the statistical process behind analyzing the age distribution of proofreaders at a publishing company. Learn how to use the Z-score formula for individual and sample mean probabilities, and how to interpret results using a Z-table.
Two-Sample T-Test: Analyzing Control vs. Supplemented Groups
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Explore the steps to conduct a two-sample t-test using a control and supplemented group. Through hypothesis testing, standard deviation, and P-value interpretation, we analyze the means of both groups to determine statistical differences.
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.
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.













