Confidence Interval (Women's Heights) Quiz
The question sheet
Reveal any answer as you study-
What confidence level does the student calculate in this Women's Heights activity?
- 80 percent
- 95 percent
- 99 percent
- 90 percent
Reveal answer
Answer: 90 percent
Source evidence
PDF page 496: • The student will calculate a 90 percent confidence interval using the given data.
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In the Women's Heights activity, the population standard deviation is known to be:
- 2.8 in.
- 15 lb.
- 3.0 in.
- 3.3 in.
Reveal answer
Answer: 3.3 in.
Source evidence
PDF page 496: known to be 3.3 in. With these values, construct a 90 percent confidence interval for your sample of 10 values. Write the confidence interval you obtained in the first space of Table 8.9.
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How many values are in each sample used to construct a confidence interval in this activity?
- 39
- 10
- 5
- 100
Reveal answer
Answer: 10
Source evidence
PDF page 496: known to be 3.3 in. With these values, construct a 90 percent confidence interval for your sample of 10 values. Write the confidence interval you obtained in the first space of Table 8.9.
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Table 8.8 in this activity lists the heights of how many women?
- 100
- 39
- 10
- 50
Reveal answer
Answer: 100
Source evidence
PDF page 496: Table 8.8 Heights of 100 Women (in
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A second objective is to relate the confidence level to the percentage of intervals that contain what?
- The population mean
- The sample size
- The standard deviation
- The sample mean
Reveal answer
Answer: The population mean
Source evidence
PDF page 496: • The student will determine the relationship between the confidence level and the percentage of constructed
PDF page 496: intervals that contain the population mean.
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After collecting many confidence intervals, students count how many contain what value?
- The sample size n
- The error bound
- The population mean μ
- The sample mean μ
Reveal answer
Answer: The population mean μ
Source evidence
PDF page 497: confidence intervals, count how many of them contain the population mean μ; i.e., for how many intervals does the value of μ lie between the endpoints of the confidence interval?
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Which best interprets 'the population mean lies within the confidence interval'?
- μ equals the standard deviation
- μ is outside the endpoints
- μ is between the interval endpoints
- μ equals the sample mean exactly
Reveal answer
Answer: μ is between the interval endpoints
Source evidence
PDF page 497: population mean lies within the confidence interval. Using complete sentences, explain what we mean by this phrase.
PDF page 497: confidence intervals, count how many of them contain the population mean μ; i.e., for how many intervals does the value of μ lie between the endpoints of the confidence interval?
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The activity asks students to count how many of the 100 data values lie within their interval and compare to what?
- 50 percent
- 90 percent
- 95 percent
- 100 percent
Reveal answer
Answer: 90 percent
Source evidence
PDF page 497: given (the heights of women) and count how many of the data values lie within the confidence interval that you generated based on that data. How many of the 100 data values lie within your confidence interval? What percentage is this? Is this percentage close to 90 percent?
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Without knowing μ, can you be certain your interval actually contains μ?
- Only for 90% intervals
- Yes, always
- No, not for certain
- Only with n=100
Reveal answer
Answer: No, not for certain
Source evidence
PDF page 497: Without knowing the population mean μ, would you have any way of knowing for certain whether your interval actually contained the value of μ? Explain.
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A confidence interval is an interval estimate for what?
- An unknown population parameter
- The sample size
- A fixed constant
- A known sample value
Reveal answer
Answer: An unknown population parameter
Source evidence
PDF page 498: confidence interval (CI) an interval estimate for an unknown population parameter. This depends on the following:
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If CL = 90 percent, in about how many of 100 samples does the interval enclose the true parameter?
- 50
- 90
- 10
- 100
Reveal answer
Answer: 90
Source evidence
PDF page 498: confidence level (CL) the percentage expression for the probability that the confidence interval contains the true population parameter; for example, if the CL = 90 percent, then in 90 out of 100 samples, the interval estimate will enclose the true population parameter degrees of freedom (df) the number of objects in a sample that are free to vary error bound for a population mean (EBM) the margin of error; depends on the confidence level, sample size, and known or estimated population standard deviation
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What term names the margin of error for a population mean?
- EBP
- df
- CL
- EBM
Reveal answer
Answer: EBM
Source evidence
PDF page 498: confidence level (CL) the percentage expression for the probability that the confidence interval contains the true population parameter; for example, if the CL = 90 percent, then in 90 out of 100 samples, the interval estimate will enclose the true population parameter degrees of freedom (df) the number of objects in a sample that are free to vary error bound for a population mean (EBM) the margin of error; depends on the confidence level, sample size, and known or estimated population standard deviation
High School Statistics
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