Module 9 Flashcards
The region of rejection typically appears \_\_\_\_\_ of the sampling distribution? A) Above the mean B) Below the mean C) In the Center D) At the extremes
D) At the extremes
If the sample mean is of the kind that could readily occur when the null hypothesis is true, we will A) Reject H₀ B) Retain H₀ C) Suspend judgment D) Change the level of significance
B) Retain H₀
The criterion by which a decision is made about the null hypothesis is called A) The level of significance B) Alpha C) Either of the above D) The alternative hypothesis
C) Either of the above
According to the information contained in the sampling distribution, we reject the null hypothesis if the probability of obtaining such a sample mean is A) Known B) Estimated C) Low D) High
C) Low
The null hypothesis is always A) Specific B) Retained for deviant sample results C) The hypothesis of no difference D) (A) and (B) above
A) Specific
Assume σ is known. What are the critical values for testing H₀: μ = 200 against H₁: μ ≠ 200 with α = .04? A) ±1.75 B) ±1.41 C) ±2.05 D) ±1.67
C) ±2.05
Assume σ is unknown. What are the critical values for testing
H₀: μ = 60 against H₁: μ ≠ 60 with α = .08?
A) ±1.75
B) ±1.41
C) ±2.05
D) ±1.67
A) ±1.75
In order to test H₀, we must assume
A) A normal distribution shape
B) It is true
C) A level of significance of 0.05 or 0.01
D) Representative sample results (except for sampling error)
B) It is true
When the value of α is changed from 0.05 to 0.01,
A) The greater the desireability of using a two-tailed test
B) The greater the value of z required to reject the null hypothesis
C) The smaller the region of retention
D) We should be less confident about our decision if that decision is to reject the null hypothesis
B) The greater the value of z required to reject the null hypothesis
In testing a hypothesis about the population mean, the sample mean is compared with
A) Sample means that would occur when the hypothesis is false
B) Sample means that would occur when the hypothesis is true
C) Various population means that could occur
D) Means of samples for all possible values of n
B) Sample means that would occur when the hypothesis is true
The statistical hypothesis to be tested is called the A) Trial hypothesis B) Directional hypothesis C) Alternative hypothesis D) Null hypothesis
D) Null hypothesis
In testing a hypothesis about a mean, the mean of the sampling distribution is taken to be A) The value stated in H₀ B) The value stated in H₁ C) Either (A) or (B) D) Neither (A) nor (B)
A) The value stated in H₀
When the value of α is changed from 0.05 to 0.01:
A) The standard error of the mean is reduced.
B) The significance level is lowered.
C) The more deviant a sample mean must be before it leads to rejection of the null hypothesis.
D) Both (b) and (c).
D) Both (b) and (c)
If the outcome of a test is significant at the .01 level, it
A) Also will be significant at the 0.05 level
B) Will not be significant at the 0.05 level
C) May be significant at the 0.05 level
D) Probably will not be significant at the 0.05 level
A) Also will be significant at the 0.05 level
The assertion of statistical significance
A) Means that H₀ could well be true
B) Indicates all other hypotheses have been eliminated
C) Is meaningful only in connection with the level of significance used
D) Indicates the statistical importance of the results
C) Is meaningful only in connection with the level of significance used
Given: x̄ = 102, H₀: μ = 100, H₁: μ ≠ 100. If H₀ is retained, this means that
A) No other H₀ could be true
B) Other null hypotheses are probably not true
C) H₀ is probably true
D) H₀ could be true, but so could other null hypotheses
H₀ could be true, but so could other null hypotheses
Statistical significance means
A) Rejection of H₁
B) A significant finding, after the statistical analysis
C) An important difference between the hypothesized and the population value
D) Rejection of H₀
D) Rejection of H₀
The choice between a one-tailed test and a two-tailed test
A) Will affect the way H₀ is stated
B) Should be made after learning the location of x̄
C) Is determined by the logic of the study rather than by the outcome of the data
D) Is a matter of taste; some statisticians prefer (B) and some prefer (C)
C) Is determined by the logic of the study rather than by the outcome of the data
“One-tailed” is to “two-tailed” as: A) “Significant” is to “nonsignificant” B) “p” is to “α” C) “H₀” is to “H₁” D) “Directional” is to “nondirectional”
D) “Directional” is to “nondirectional”
Assume that H₁: μ < μ₀. The statistical decision following from “p > α” is identical to that following from A) z > -zₐ B) x̄ > μ₀ C) z > -zₐ D) None of the above
A) z > -zₐ
Which, if any, need not be decided in advance of conducting the test of a null hypothesis? A) The level of significance B) The nature of H₁ C) The region of rejection D) All should be decided in advance
D) All should be decided in advance
If we test H₀: μ = 100 against H₁: μ < 100, the region of rejection will be located A) At the extreme right B) At the extreme left C) At the two extremes D) In the center
B) At the extreme left
We originally plan to use a two-tailed test but then change our mind (before collecting our data) and move to a one-tailed test. For the one-tailed test
A) The critical value will be numerically less
B) The critical value will be numerically greater
C) The value of α will be exactly half that for the two-tailed test
D) The null hypothesis will be stated differently
A) The critical value will be numerically less
For a one-tailed test (α is known), the critical values for testing a hypothesis about μ at α = .05 and α = .01 are, respectively A) 1.58 and 2.96. B) 1.65 and 2.33. C) 1.96 and 2.58. D) 1.33 and 2.64.
B) 1.65 and 2.33
For a two-tailed test (α is known), the critical values for testing a hypothesis about μ at α = .05 and α = .01 are, respectively A) 1.58 and 2.96. B) 1.65 and 2.33. C) 1.96 and 2.58. D) 1.33 and 2.64.
C) 1.96 and 2.58
Which of the following is true?
A) α specifies the size of the region of rejection, and H₀ specifies where it is to be located
B) α specifies the nature of the alternative hypothesis, and H₁ specifies where the region of rejection is to be located
C) α specifies the size of the region of rejection, and H₁ specifies where it is to be located
D) α specifies the probability of coming to a wrong conclusion when the hypothesis is false, and H₀ specifies where the region of rejection is to be located
C) α specifies the size of the region of rejection, and H₁ specifies where it is to be located
The region of rejection is determined by A) The level of significance B) The nature of the alternative hypothesis C) Both (a) and (b) D) Neither (a) nor (b)
C) Both (a) and (b)
We never assume the H₁ to be true in order to test it, because A) It is a "dummy" hypothesis B) It is not specific C) Our primary concern is with the H₀ D) All of the above
B) It is not specific
“H₀” is to “H₁” as: A) “Specific” is to “nonspecific” B) “Specified in advance” is to “specified later” C) “True” is to “false” D) “Retain” is to “reject”
A) “Specific” is to “nonspecific”
Which of the first three statements, if any, is false? H₀ is:
A) The hypothesis about which the statistical decision is made
B) Always a statement about a parameter
C) Always expressed as a point value
D) None of the above is true
D) None of the above is true
We expect the alternative hypothesis to be a: A) Particular value of a statistic B) Range of values for a statistic C) Particular value of a parameter D) Range of values for a parameter
D) Range of values for a parameter
Which of the first three statements, if any, is false? H₁ is:
A) Always a statement about a parameter
B) Expressed as a range of values
C) States whether the test is directional or nondirectional
D) None of the above is false
D) None of the above is false
Which of the following has the characteristic form of a null hypothesis? A) μ > 150 B) μ ≠ 150 C) μ = 150 D) All of the above
C) μ = 150
A type I error is committed when a: A) True null hypothesis is rejected B) False null hypothesis is retained C) True alternative hypothesis is retained D) α is higher than it should be
A) True null hypothesis is rejected
The smaller the level of significance
A) The less the probability of a Type I error
B) The less the probability of a Type II error
C) The greater the probability of a Type I error
D) The less confident we may be in whatever statistical conclusion is reached
A) The less the probability of a Type I error
Which of the following will increase the probability of making a type II error?
A) Use α = .01 rather than .05
B) Use dependent samples
C) Increase n
D) Use a one-tailed test (correct direction)
A) Use α = .01 rather than .05