Unit 10 Confidence Intervals Flashcards

1
Q

What is the parameter for a 1 sample t interval for means?

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the statistic for a 1 sample t interval for means?

A

x-bar

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the parameter for a 1 proportion z interval?

A

p

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the statistic for a 1 proportion z interval?

A

p-hat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the statistic for a 2 sample t interval for means?

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the statistic for a 2 proportion z interval?

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the 3 conditions for a confidence interval for proportions?

A
  1. We have a random sample.
  2. The population is greater than 10n.
  3. The sampling distribution is approx. normal because np-hat and nq-hat >10.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the 3 conditions for a confidence interval for means?

A
  1. We have a random sample.
  2. The population is greater than 10n.
  3. The sampling distribution is approx. normal because n > 30 OR the original population is approx. normal.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the 4 steps to create a confidence interval?

A

Don’t Cry, Cry, Cry

  1. Define Parameter (& Name your interval)
  2. Check Conditions
  3. Calculations
  4. Conclusion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are 2 ways to decrease the width of a confidence interval?

A
  1. Decrease the confidence level (decrease critical value) 2. Increase sample size, n.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the standard error of p-hat?

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the standard error of x-bar?

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Standard error is another name for _________.

A

Standard Deviation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

The 90% confidence level for the mean number of pencils a teacher has is (5, 85). Interpret the confidence level.

A

90% of the intervals constructed in this way will contain the true mean number of pencils a teacher has.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

The 90% confidence level for the mean number of pencils a teacher has is (5, 85). Interpret the confidence interval.

A

We are 90% confident that the true mean number of pencils a teacher has is between 5 and 85.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the general formula for margin of error?

A

Critical Value X Standard Deviation

17
Q

What margin of error formula will help you find the sample size needed for numerical data?

A
18
Q
A