PreparED Study Materials
Videos
Exit Poll Analysis: Education Funding Referendum Votes
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Explore the application of proportion z-tests in analyzing exit polling data. Understand how to determine the likelihood of sample results given a population proportion. Recognize the importance of considering non-sampling errors in interpreting exit poll outcomes.
Calculating Confidence Interval for Educational TV Viewership
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Learn how to determine a 90% confidence interval for the proportion of people who watch educational television based on a survey. Understand how to utilize the z-score and interpret results, guiding decisions for a television company's publicity efforts.
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.
Calcium in Chautauqua's Rain: 1990 vs. 2010 Analysis
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Explore the calcium concentration in Chautauqua's rainwater from 2010, comparing it to 1990 levels. Using statistical tests, examine normal distribution and determine significant changes. The results provide insights into environmental shifts over two decades.
Electronic Failures: Deciding Between Minor & Major Defects Cost-Effec
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Discover the intricacies of determining the cause of electronic system failures, either minor or major defects, using statistical distributions. Learn how to minimize the expected cost and make informed decisions based on soundings and loss tables
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.

















