Proportions
If the standard error calculated for a proportion hypothesis test is unexpectedly large, how might this affect the reliability of the test results?
It improves reliability only if sample mean approaches the sample median.
It has no effect on reliability as standard error is not influential in hypothesis testing.
It may decrease reliability by making it difficult to detect true differences.
It increases reliability by ensuring larger variation in captured sample data.
What is typically used to estimate the population proportion in hypothesis testing?
Population mean (μ)
Sample proportion (p-hat)
Population standard deviation (σ)
Sample mean (x-bar)
In a study with population proportion as the focus, if we want to test an unconventional claim that the true proportion is not 0.5, what initial assumption underlies our hypothesis test?
The alternative hypothesis claims that the population proportion is greater than 0.5.
The null hypothesis states there's no significant difference between sample and population proportions.
The alternative hypothesis posits the true proportion differs from any value except for 0.5.
The null hypothesis assumes that the population proportion is equal to 0.5.
If we do not have a random sample in a one-proportion z-test, can we infer anything about the population?
No, we cannot infer anything about the population as the sample is likely to be unbiased
Yes, we can make inferences about the population as the sample is likely to be unbiased
Yes, we can make inferences about the population as the sample is likely to be biased
No, we cannot infer anything about the population as the sample is likely to be biased
In constructing a confidence interval for a population proportion where and are both greater than ten, which type of distribution should be used?
Poisson distribution given discrete event occurrences over an interval are being counted.
T-distribution since we're estimating an unknown parameter based on sample data.
Normal distribution due to large enough sample size satisfying conditions for approximation.
Binomial distribution because it describes the number of successes in n independent Bernoulli trials.
A study claims that after implementing new teaching methods nationwide, student performance improved significantly; assuming previous performance rates were known precisely at , which aspect would compromise validity if overlooked during hypothesis testing?
Inherent variability within student performance masked by averaging scores.
Miscalculation involving critical values stemming from utilizing unconventional significance levels.
Sample selection biases affecting representativeness across various educational contexts.
Failure in addressing potential ethical concerns related directly back towards data collection methodologies.
What symbol represents the alternative hypothesis in hypothesis testing?
(mu)
or
(sigma squared)
or

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In an experiment testing whether a new teaching method increases standardized math scores among middle schoolers, what values might be appropriate for the researcher to use as the significance level ?
Lower levels like may unnecessarily complicate results by demanding extreme evidence before rejection.
A conservative approach of choosing a moderately low but not excessively stringent value such as provides a balance between detecting effects and avoiding mistakes.
Using a very high alpha level such as can increase the chances of committing a Type II error while decreasing the power (false positive rate) incorrectly reject the true null.
A common choice like , , or are possible choices depending on the desired strictness against Type I errors.
Considering students' preference for lunch options at school with two choices available, what statistical error does one risk by conducting multiple tests comparing each option separately against all others rather than simultaneously considering both options?
Handling comparisons separately risks inflating Type I errors due to multiplicity without adjusting significance levels across simultaneous tests.
By conducting separate tests instead, sample sizes effectively decrease leading to potentially inconclusive results.
Separate tests eliminate chances of committing any statistical errors compared to a joint approach provided data randomization is adhered to properly.
One risks encountering confounding variables influencing preferences inadvertently favoring whichever lunch option tested first.
A study wants to determine if more than half of community members support new public park funding; if their initial survey reports exactly half in favor from an adequate sample size, what value would their test statistic be closest to?
One because difference between proportions yields minimal variance.
Zero because observed proportion does not equal hypothesized value.
Negative one indicating strong opposition to public park funding.
Zero because observed proportion equals hypothesized value.