Means
What is the effect of performing a one-tailed test instead of a two-tailed test?
Decreased power and increased risk of a type I error
Decreased power and decreased risk of a type I error
Increased power and increased risk of a type I error
Increased power and decreased risk of a type I error
When summarizing data, what term describes the average distance between each data point and the mean?
Margin of error
Variance
Range
Standard deviation
Which assumption must not be violated to perform a valid test for a population mean when using a large enough sample size?
The sampled observations must be independent.
There is an unequal variance in two populations being compared.
All observations come from populations with different shapes.
Data points are collected without random sampling or assignment.
What does the p-value represent in a hypothesis test?
The degrees of freedom for the test
The difference between the sample mean and the hypothesized mean
The standard deviation of the sample
The likelihood of obtaining the observed results by chance alone
Which consideration can affect power of the test when conducting hypothesis testing?
The directionality specified before running calculations
The labeling system used on observed outcomes
The participants' understanding of their role during data collection
The significance level chosen
What does it indicate if we obtain a p-value lower than our significance level when testing whether there's an increase in average time spent on homework?
We fail to reject the null hypothesis and conclude there’s no increase in average time on homework.
The test was inconclusive; hence we cannot make any inference about students' homework time.
We reject the null hypothesis suggesting evidence for increased average time on homework.
We confirm that our sample data perfectly represents all students’ average time spent on homework.
What is often used as an estimate of population variance when calculating standard errors for hypothesis tests concerning means?
Sample variance ()
Sample interquartile range
Sample range
Population variance

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If a hypothesis test for a population mean results in a p-value of 0.03, what is the best interpretation when using a significance level of 0.05?
There is not enough evidence to reject the null hypothesis.
The p-value indicates that the null hypothesis is true.
The test statistic is greater than the critical value.
There is sufficient evidence to reject the null hypothesis.
What should researchers use to minimize variability in their estimates when testing hypotheses regarding population means?
A diverse range of test statistics
A wider confidence interval
More variables in their model
A larger sample size
What assumption must be met regarding sample distribution before performing most parametric tests on population means?
The sampling distribution should be approximately normal.
Each individual observation within the sample should follow its own distinct normal distribution.
The samples should come from distributions with identical skewness and kurtosis measures only.
The sampling distribution must be perfectly uniform across all values.