In a major urban area, the percentage of male drivers between the ages of 19 and 29 who did not regularly use seatbelts was 28%.
After a major radio and television campaign and stricter enforcement by the local police, researchers want to know if the percentage of male drivers between the ages of 19 and 29 who did not regularly use seatbelts has decreased.
They poll a random sample of 100 males between the ages of 19 and 20 and find the percentage who didn't wear their seatbelt was 24%.
Identify the population, parameter, sample and statistic.
| Draggable item | arrow_right_alt | Corresponding Item |
|---|---|---|
28% | arrow_right_alt | Population |
True proportion of males between 19 & 29 who don't wear seatbelts | arrow_right_alt | Sample |
100 male drivers between the ages of 19 & 29 | arrow_right_alt | Statistic |
All male drivers between the ages of 19 & 29 | arrow_right_alt | Parameter |
24% didn't wear seatbelts | arrow_right_alt |
In a major urban area, the percentage of male drivers between the ages of 19 and 29 who did not regularly use seatbelts was 28%.
After a major radio and television campaign and stricter enforcement by the local police, researchers want to know if the percentage of male drivers between the ages of 19 and 29 who did not regularly use seatbelts has decreased.
They poll a random sample of 100 males between the ages of 19 and 20 and find the percentage who didn't wear their seatbelt was 24%.
Identify the null and alternative hypothesis:
Approximately 91% of all adults in South Korea have a cell phone. In a simple random sample of 200 adults in the United States, 171 owned cell phones.
Is there convincing evidence to suggest the proportion of adults who own cell phones in the U.S. is lower than the proportion of adults who own cell phones in South Korea?
Conduct a significance test using the 4-step process.
STATE: select what must be stated, there are 4.
Approximately 91% of all adults in South Korea have a cell phone. In a simple random sample of 200 adults in the United States, 171 owned cell phones.
Is there convincing evidence to suggest the proportion of adults who own cell phones in the U.S. is lower than the proportion of adults who own cell phones in South Korea?
Conduct a significance test using the 4-step process.
What is the sample statistic? Round to three places
What is the symbol?
Approximately 91% of all adults in South Korea have a cell phone. In a simple random sample of 200 adults in the United States, 171 owned cell phones.
Is there convincing evidence to suggest the proportion of adults who own cell phones in the U.S. is lower than the proportion of adults who own cell phones in South Korea?
You are going to conduct a significance test using the 4-step process.
First: What is the alpha level we use if none is specified?
Approximately 91% of all adults in South Korea have a cell phone. In a simple random sample of 200 adults in the United States, 171 owned cell phones.
Is there convincing evidence to suggest the proportion of adults who own cell phones in the U.S. is lower than the proportion of adults who own cell phones in South Korea?
Conduct a significance test using the 4-step process.
What are the hypothesis for this significance test?
Ho:
Ha:
Move each answer into the correct category.
p>0.91
p=0.855
p<0.91
p=0.91
p<0.855
Incorrect Answers
Approximately 91% of all adults in South Korea have a cell phone. In a simple random sample of 200 adults in the United States, 171 owned cell phones.
Is there convincing evidence to suggest the proportion of adults who own cell phones in the U.S. is lower than the proportion of adults who own cell phones in South Korea?
Conduct a significance test using the 4-step process.
PLAN:
What conditions need to be met before conducting the significance test?
PLAN:
Explain if the conditions are met and how you know.
DO:
What is the standardized test statistic for this significance test?
Round to two places past the decimal.
What is the p-value for this significance test?
Keep all places past the decimal.
Interpret the p-value from the previous question.
Hint: this is Lesson 8.1
What is your conclusion based on an alpha level of 0.05?
Select three correct answers.
You just calculated a 95% confidence interval for p.
Explain how this interval gives results consistent with the significance test that was just performed.
Hint: does the confidence interval support the sig. test results? If so why? If not, why?
Select three responses to answer & explain.
What is a Type I Error in this situation?
What is a Type II Error in this situation?
We think that the proportion of adults in the US who have a cell phone is more than 91% but really it is equal to 91%.
We think the proportion of adults in the US who have cell phones is equal to 91% but really it is not.
We think that the proportion of adults in the US who have a cell phone is less than 91% but really it is equal to 91%.
Type I Error
Type II Error
Incorrect Answer