A Random Sample From A Population

AThe sample mean does not occur very often by chance in the sampling distribution of means and probably did not come from the given population
BThe sample mean occurs very often by chance in the sampling distribution of means and probably did not come from the given population
CThe sample mean does not occur very often by chance in the sampling distribution of means but probably did come from the given population
DThe sample mean occurs very often by chance in the sampling distribution of means and probably did come from the given population

2What do we call that portion of the sampling distribution in which values are considered too unlikely to have occurred by chance?
ARegion of criterion value
BRegion of critical value
CRegion of rejection
DCritical value

3Suppose you take a piece of candy out of a jar, look to determine its color, then put it back into the jar before you randomly select the next piece of candyThis type of sampling is called
Aan independent event
Bsampling with replacement
Ca dependent event
Dsampling without replacement

4There are 26 red cards in a playing deck and 26 black cardsThe probability of randomly selecting a red card or a black card is 26/52 = 050Suppose you randomly select a card from the deck five times, each time replacing the card and reshuffling before the next pickEach of the five selections has resulted in a red cardOn the sixth turn, the probability of getting a black card
Ahas got to be low because you’ve gotten so many red cards on the previous turns
Bhas got to be high because you’ve gotten so many red cards on the previous turns
Cis the same as it has always been if the deck is a fair deck
Dneeds to be recomputed because you are sampling with replacement

5What can you conclude about a sample mean that falls within the region of rejection?
AThe sample probably represents some population other than the one on which the sampling distribution was based
BThe sample represents the population on which the sampling distribution was based
CAnother sample needs to be collected
DThe sample should have come from the given population

6What can we conclude when the absolute value of a z-score for a sample mean is larger than the critical value?
AThe random selection procedure was conducted improperly
BThe sample mean is reasonably likely to have come from the given population by random sampling
CThe sample mean represents the particular raw score population on which the sampling distribution is based
DThe sample mean does not represent the particular raw score population on which the sampling distribution is based

7When rolling a pair of fair dice, the probability of rolling a total point value of 7 is 017If you rolled a pair of dice 1,000 times and the point value of 7 appeared 723 times, what would you probably conclude?

AThis is not so unlikely as to make you doubt the fairness of the dice
BAlthough not impossible, this outcome is so unlikely that the fairness of these dice is questionable
CSince the total point value of 7 has the highest probability of any event in the sampling distribution, this is an extremely likely outcome
DIt is impossible for this to happen if the dice are fair

8 What is the appropriate outcome of a z-test?
AReject and accept
BReject and accept
CReject ; accept
DFail to reject ; accept

9The null hypothesis describes the
Asample statistic and the region of rejection
Bsample statistic if a relationship does not exist in the sample
Cpopulation parameters represented by the sample data if the predicted relationship exists
Dpopulation parameters represented by the sample data if the predicted relationship does not exist

10In a one-tailed test, is significant only if it lies
Anearer than and has a different sign from
Bin the tail of the distribution beyond and has a different sign from
Cnearer than and has the same sign as
Din the tail of the distribution beyond and has the same sign as

11The key difference between parametric and nonparametric procedures is that parametric procedures
Ado not require that stringent assumptions be met

Brequire that certain stringent assumptions be met
Care used for population distributions that are skewed
Dare used for population distributions that have nominal scores

12Which of the following accurately defines a Type I error?
ARejecting when is true
BRejecting when is false
CRetaining when is true
DRetaining when is false

13If and what is the value of
A258
B052
C258
D078

14What happens to the probability of committing a Type I error if the level of significance is changed froma=0.01 toa=0.05?
AThe probability of committing a Type I error will decrease
BThe probability of committing a Type I error will increase
CThe probability of committing a Type I error will remain the same
DThe change in probability will depend on your sample size

15Suppose you perform a on a correlation between the number of books read for enjoyment and the number of credit hours taken, using 32 participantsYour is 015, which is not a significant correlation coefficientWhich of the following is the correct way to report this finding?
Ar(32) = 015, p > 005
Br(31) = 015, p > 005
Cr(30) = 015, p < 005
Dr(30) = 015, p > 005

16Which of the following would increase the power of a significance test for correlation?
AChangingafrom 005 to 001
B. Increasing the variability in the Y scores
C. Changing the sample size from N = 25 to N = 100
D. Changing the sample size from N = 100 to N = 25

17If a sample mean has a value equal to , the corresponding value of t will be equal to
A+10
B00
C10
D+20

18What is ?
AThe estimated population standard deviation
BThe population standard deviation
CThe estimated standard error of the mean
DThe standard error of the mean

19In a for a correlation predicted to be positive, the null
hypothesis is ___________ and the alternative hypothesis is __________
A. Ho: 0; Ha: > 0
B. Ho: < 0; Ha: 0
C. Ho: = 0; Ha: > 0
D. Ho: < 0; Ha > 0

20How is the t-test for related samples performed?
ABy conducting a on the sample of difference scores
BBy conducting an on the sample of difference scores
CBy converting the scores to standard scores and then performing a related samples t-test
DBy measuring the population variance and testing it using an independent samples t-test

21What does the alternative hypothesis state in a two-tailed independent samples
experiment?

Ho: mu1-mu2=0
22One way to increase power is to maximize the difference produced by the two conditions in the experimentHow is this accomplished?
AChangeafrom 005 to 001
BChange the size of N from 100 to 25
CDesign and conduct the experiment so that all the subjects in a sample are treated in a consistent manner
DSelect two very different levels of the independent variable that are likely to produce a relatively large difference between the means

23Suppose you perform a two-tailed independent samples t-test, usinga= 005, with 15 participants in one group and 16 participants in the other groupYour is 456, which is significantWhich of the following is the correct way to report this finding?
At(31) = 456; p< 005
Bt(29) = 456; p < 005
Ct(29) = 456; p > 005
Dt(29) = 456; p = 005

24Suppose that you measure the IQ of 14 subjects with short index fingers and the IQ
of 14 subjects with long index fingersYou compute an independent samples t-test,
and the is 029, which is not statistically significantWhich of the following is the
most appropriate conclusion?
AThere is no relationship between length of index finger and IQ
BThere is a relationship between length of index finger and IQ
CThe relationship between length of index finger and IQ does not exist
DWe do not have convincing evidence that our measured relationship between length of index finger and IQ is due to anything other than sampling error

25The assumptions of the t-test for related samples are the same as those for the test for independent samples except for requiring
Athat the dependent variable be measured on an interval or ratio scale
Bthat the population represented by either sample form a normal distribution
Chomogeneity of variance
Dthat each score in one sample be paired with a particular score in the other sample

Use SPSS and the provided data set to answer the questions below:
26Test the age of the participants (AGE1) against the null hypothesis H 0 = 34Use a
one-sample t-testHow would you report the results?
At = -1862, df = 399, p >05
Bt = -1862, df = 399, p <05
Ct = 1645, df = 399, p >05
Dt = 1645, df = 399, p <05

27Test to see if there is a significant difference between the age of the participant and the age of the partnerUse a paired-sample t-test and an alpha level of 1%How would you interpret the results of this test?
AThe partners are significantly older than the participants
BThe partners are significantly younger than the participants
CThe age of the participants and partners are not significantly different
DSometimes the partners are older, sometimes the participants are older

28Look at the correlation between Risk-Taking (R) and Relationship Happiness (HAPPY)Use the standard alpha level of 5%How would you describe the relationship?
AThe relationship is non-significant
BThere is a significant negative relationship
CThere is a significant positive relationship
DThe correlation is zero

29If you randomly chose someone from this sample, what is the chance that they
described their relationship as either Happy or Very Happy?
A32%
B37%
C56%
D69%

30Perform independent sample t-tests on the Lifestyle, Dependency, and Risk-Taking
scores (L, D, and R) comparing men and women (GENDER1)Use p &lt;05 as your
alpha levelOn each of the three scales, do men or women have a significantly
higher score?
ALifestyle: Men, Dependency: Women, Risk-Taking: Men
BLifestyle: Not significantly different, Dependency: Women, Risk-Taking: Men
CLifestyle: Women, Dependency: Women, Risk-Taking: Men
DLifestyle: Men, Dependency: Men, Risk-Taking: Not significantly different