Skip to main content
Ch. 8 - Hypothesis Testing
Triola - Elementary Statistics 14th Edition
Triola14th EditionElementary StatisticsISBN: 9780137366446당신이 사용하는 게 아니라요?교과서 변경
8장, 문제 8.1.20a

Finding Critical Values
In Exercises 17–20, refer to the information in the given exercise and use a 0.05 significance level for the following.


a. Find the critical value(s).
b. Should we reject H0 or should we fail to reject H0?


Exercise 16

검증된 단계별 안내
1
Step 1: Identify the type of hypothesis test being conducted (e.g., one-tailed or two-tailed). This is determined by the alternative hypothesis (H1). If H1 specifies a direction (e.g., greater than or less than), it is a one-tailed test. If it does not specify a direction (e.g., not equal to), it is a two-tailed test.
Step 2: Determine the degrees of freedom (if applicable). For example, in a t-test, the degrees of freedom are typically calculated as df = n - 1, where n is the sample size.
Step 3: Use the significance level (α = 0.05) and the type of test (one-tailed or two-tailed) to find the critical value(s) from the appropriate statistical table (e.g., z-table for a z-test, t-table for a t-test, or chi-square table for a chi-square test). For a two-tailed test, divide α by 2 to find the critical values for both tails.
Step 4: Compare the test statistic (calculated from the sample data) to the critical value(s). If the test statistic falls in the critical region (beyond the critical value(s)), reject the null hypothesis (H0). Otherwise, fail to reject H0.
Step 5: Conclude the hypothesis test by interpreting the result in the context of the problem. For example, if H0 is rejected, state that there is sufficient evidence to support the alternative hypothesis (H1). If H0 is not rejected, state that there is insufficient evidence to support H1.

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
영상 길이:
3m
도움이 되었나요?

주요 개념

질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.

Critical Values

Critical values are the threshold points that define the boundaries for rejecting the null hypothesis in hypothesis testing. They are determined based on the significance level (alpha), which indicates the probability of making a Type I error. For a significance level of 0.05, critical values can be found using statistical tables or software, depending on the distribution being analyzed (e.g., normal, t-distribution).
추천 영상:
05:50
Critical Values: t-Distribution

Null Hypothesis (H0)

The null hypothesis (H0) is a statement that there is no effect or no difference, and it serves as the default assumption in hypothesis testing. Researchers aim to gather evidence against H0 to support an alternative hypothesis (H1). The decision to reject or fail to reject H0 is based on the comparison of test statistics to critical values.
추천 영상:
가이드 코스
06:21
Step 1: Write Hypotheses

Significance Level

The significance level, denoted as alpha (α), is the probability threshold set by the researcher for determining whether to reject the null hypothesis. A common significance level is 0.05, which implies a 5% risk of concluding that a difference exists when there is none (Type I error). This level helps in making decisions based on the p-value obtained from statistical tests.
추천 영상:
가이드 코스
04:46
Step 4: State Conclusion Example 4
관련 실천
교과서 질문

Perception and Reality In a presidential election, 308 out of 611 voters surveyed said that they voted for the candidate who won (based on data from ICR Survey Research Group). Use a 0.05 significance level to test the claim that among all voters, the percentage who believe that they voted for the winning candidate is equal to 43%, which is the actual percentage of votes for the winning candidate. What does the result suggest about voter perceptions?

122
views
교과서 질문

Identifying H0 and H1

In Exercises 5–8, do the following:


a. Express the original claim in symbolic form.

b. Identify the null and alternative hypotheses.


Systolic Blood Pressure Claim: Healthy adults have systolic blood pressure levels with a standard deviation greater than 5 mm Hg. Sample data: Data Set 1 “Body Data” in Appendix B shows that for 300 healthy adults, the systolic blood pressure amounts have a standard deviation of 15.85 mm Hg.

69
views
교과서 질문

Finding Critical Values

In Exercises 17–20, refer to the information in the given exercise and use a 0.05 significance level for the following.


a. Find the critical value(s).

b. Should we reject H0 or should we fail to reject H0?


Exercise 15

85
views
교과서 질문

Statistical Literacy and Critical Thinking

In Exercises 1–4, use the results from a Hankook Tire Gauge Index survey of a simple random sample of 1020 adults. Among the 1020 respondents, 86% rated themselves as above average drivers. We want to test the claim that more than 3/4 of adults rate themselves as above average drivers.


Number and Proportions


a. Identify the actual number of respondents who rated themselves as above average drivers.

106
views
교과서 질문

Identifying H0 and H1

In Exercises 5–8, do the following:


a. Express the original claim in symbolic form.

b. Identify the null and alternative hypotheses.


Light Year Claim: Most adults know that a light year is a measure of distance. Sample data: A Pew Research Center survey of 3278 adults showed that 72% knew that a light year is a measure of distance.

143
views
교과서 질문

RESAMPLING

a. In general, what does it mean to “resample” the following data set consisting of wait times (minutes) of customers waiting in line for the Space Mountain ride at Walt Disney World: 50, 25, 75, 35, 50?

165
views