#1
What is the null hypothesis in statistical hypothesis testing?
The hypothesis that there is no significant difference or relationship
The alternative hypothesis
The hypothesis that there is a significant difference or relationship
The hypothesis that there is a perfect correlation
#2
In hypothesis testing, what does p-value represent?
Probability of observing the data if the null hypothesis is true
Probability of rejecting the null hypothesis when it is true
Probability of accepting the null hypothesis when it is true
Probability of observing the data if the alternative hypothesis is true
#3
What is the Type I error in hypothesis testing?
Rejecting the null hypothesis when it is true
Failing to reject the null hypothesis when it is false
Accepting the null hypothesis when it is true
Rejecting the alternative hypothesis when it is true
#4
Which of the following is NOT a requirement for performing a hypothesis test?
Random sampling
Normality of data distribution
Independence of observations
Equal variances in the samples
#5
Which statistical test is appropriate for comparing the means of two independent groups?
Paired t-test
One-sample t-test
Independent samples t-test
ANOVA
#6
What is the formula for the test statistic in a one-sample z-test for proportions?
(p - P) / sqrt(P * (1 - P) / n)
(p̂ - P) / sqrt(p̂ * (1 - p̂) / n)
(p̂ - μ) / sqrt(p̂ * (1 - p̂) / n)
(p - μ) / sqrt(p * (1 - p) / n)
#7
What is the purpose of a confidence interval?
To estimate the population parameter
To determine the level of significance
To summarize the sample data
To calculate the p-value
#8
In hypothesis testing, what does the power of a test measure?
The probability of Type I error
The probability of Type II error
The probability of correctly rejecting the null hypothesis
The probability of incorrectly accepting the null hypothesis
#9
What is the formula for the test statistic in a one-sample t-test for means?
(x̄ - μ) / (s / sqrt(n))
(x̄ - μ) / (s * sqrt(n))
(x̄ - μ) / (s / n)
(x̄ - μ) / (s * n)
#10
In statistical hypothesis testing, what does a confidence level represent?
The probability of making a Type I error
The probability of making a Type II error
The percentage of confidence in the estimation
The significance level for rejecting the null hypothesis
#11
What is the critical value used for hypothesis testing typically based on?
Sample size and level of significance
Mean and standard deviation
Sample size and population proportion
Confidence interval
#12
When performing a two-sample t-test, what assumption is made about the variances of the two groups?
They must be equal
They must be significantly different
They can be equal or unequal
There is no assumption about the variances
#13
Which of the following is true about a one-tailed test compared to a two-tailed test?
A one-tailed test has a larger critical value.
A one-tailed test is more conservative.
A one-tailed test has a smaller rejection region.
A one-tailed test is more suitable for non-directional hypotheses.
#14
What is the correct interpretation of a 95% confidence interval for a population mean?
There is a 95% chance that the population mean lies within the interval.
95% of the population values lie within the interval.
In 95% of repeated sampling, the calculated interval will contain the true population mean.
The population mean lies exactly at the midpoint of the interval with 95% certainty.
#15
Which statistical test is appropriate for comparing the means of more than two independent groups?
Independent samples t-test
Paired t-test
ANOVA
Chi-square test
#16
Which of the following is NOT a requirement for performing a two-sample t-test?
Both samples are independent.
The populations have equal variances.
The populations have normal distributions.
The samples are randomly selected.