Flag this Question Question 11 What does the second column in afrequency table show? Group of answer choices
a)categories (or levels) of the variable
b)probability of the variable
c)frequencies
d)percentages
Flag this Question Question 122 pts A college instructor wantsto know the amount of time her students spend on studying every dayso she collected the information from everyone in her class. Thedata yielded a mean of 90 minutes and a standard deviation of 8minutes. What is the variance?
Group of answer choices
64
8
2.
83
Question 132 pts
What is the standard deviation of the sample that consists of 3,5, 9, 11, 15?
Group of answer choices
4.27
1.72
18.24
91.2
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Question 142 pts
You randomly select someone from a group of 20. Eight people inthe group are females. What is the probability that the person youdraw is a male?
Group of answer choices
.73
.60
.40
.12
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Question 152 pts
What minimum Z score does a student need to get to be ranked inthe top 5% of her/his class? (Use the Z table)
Group of answer choices
around 2.33
around 1.28
around 1.65
around 0.05
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Question 162 pts
Explain why we make an inference about a population using asample.
Group of answer choices
It is typically not possible or practcal to study the entirepopulation of interest.
Samples are easier to analyze using mathematical analysis.
A sample is often vastly different of the population from whichit is drawn.
We can's study a population of interest directly because itreally does not exist.
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Question 172 pts
Meditation is proposed by some to improve the overall quality ofsleep. A researcher wants to examine the effect of meditation onthe number of minutes spent in deep sleep. She is not sure,however, if meditation will increase or decrease the number ofminutes in deep sleep. Should she conduct a one-tailed ortwo-tailed hypothesis test, and why?
Group of answer choices
One-tailed because only one variable, sleep, is examined
One-tailed because meditation is proposed to improve sleepquality.
Two-tailed because there are two variables—whether or not peoplemeditate and whether deep sleep is increased.
Two-tailed because the researcher is interested in any effect ofmeditation on deep sleep, increase or decrease.
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Question 182 pts
In a housing project there are 180 households in which Englishis usually spoken, 80 in which Spanish is usually spoken, and 40 inwhich the language is other than English or Spanish. A researcherapproaches a house at random to conduct an interview. What is thechance that the usual language in that household will NOT beEnglish?
Group of answer choices
.60
.33
.40
.12
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Question 192 pts
Interpret this statement: \"We fail to reject the null hypothesisat alpha level of .05.\"
Group of answer choices
The probability was less than .05 that a sample like this couldhave been obained when the null hypothesis was true.
The probability was more than .05 that a sample like this couldhave been obtained when the null hypothesis was true.
The probability was less than .05 that a sample like this couldhave been obained when the null hypothesis was false.
The probability was more than .05 that a sample like this couldhave been obained when the null hypothesis was false.
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Question 202 pts
In a single throw of a die, what is the probability of attaininga number that is 2 or lower?
Group of answer choices
.67
.50
.20
.33
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Question 212 pts
What is a valid reason for choosing a two-tailed test even whena given direction can be predicted?
Group of answer choices
Statistical programs are set to default to two-tailed tests.
One-tailed tests are more effective in preventing Type Ierrors.
Two-tailed tests allow for the possibility that the findingcould be in either direction.
A two-tailed test is more likely to produce a significantresult.
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Question 222 pts
Why is a one-tailed test considered a more lenient test than atwo-tailed test on a sample of data?
Group of answer choices
The alpha is multiplied by two in order to figure the size ofthe significance area in each tail for a two-tailed test, resultingin more alpha in a two-tailed test.
The tail areas in a two-tailed test are combined in one tail ina one-tailed test, making the critical value less extreme in aone-tailed test than in a two-tailed test.
The one-tailed test has only one critical value, and thetwo-tailed test has two critical values that both need to beexceeded.
A one-tailed test only tests one hypothesis, but a twotwo-tailed test tests two hypotheses.
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Question 232 pts
How does a two-tailed test compared to a one-tailed test whengiven a sample statistic and a fixed alpha level?
Group of answer choices
The critical value to be compared to the statistic would be lessextreme with a two-tailed test.
The critical value to be compared to the statistic would be moreextreme with a two-tailed test.
The total significance area in the comparison distribution islarger in a two-tailed test.
The total significance area in the comparison distribution issmaller in a one-tailed test.
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Question 242 pts
The time spent on an exam by a class of 100 students is normallydistributed with a mean of 50 minutes and a standard deviation of 8minutes. Using the percentage approximations for the normal curve,what is the percentage of the population of all exam takers thatwould spend between 50 to 62 minutes on the exam? (Use of Z tableis necessary)
Group of answer choices
41.92%
43.32%
8.08%
6.68%
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Question 252 pts
What is the probability of drawing a score from a normaldistribution of scores that can be converted into a Z score between+1 and -2? (Use the Z table)
Group of answer choices
.9544
.6826
.3414
.8185
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Question 262 pts
A graduating class in a local high school were surveyed, and 60%of the students have decided to attend Arizona State University. IfI randomly draw a student from the graduating class, what is theprobability that the chosen student will be attending ASU?
Group of answer choices
.40
40%
.60
60%
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Question 272 pts
What happens as the overlap between the distribution ofpopulation 2 and the inferred distribution of population 1increases?
Group of answer choices
The effect size is smaller.
The effect size is larger.
The significance level rises.
The significance level falls.
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Question 282 pts
Why would a researcher complete a power analysis beforeconducting a study?
Group of answer choices
To determine the number of participants required for thestudy.
To determine whether the study should be conducted or not.
To determine the alpha level for the study.
To determine whether to conduct a one-tailed or a two-tailedtest with the data.
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Question 292 pts
The raw effect size of a study be converted to a standardizedeffect size by _______________________.
Group of answer choices
dividing the difference between the two population means by thepopulation standard deviation.
dividing the difference between the two population means by thesquare root of N
dividing the difference between the two population means by thestandard error of the sampling distribution
dividing the difference between the two population means by thesample size
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Question 302 pts
It is hypothesized that bird owners have fewer doctor's visitscompared to the general population. To conduct a one-tailedhypothesis test, the researcher sets the α (significance) level at.05. What should be the critical Z value based on the Z table?
Group of answer choices
1.96
-1.645
+1.96 and -1.96
-1.65 and +1.65
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Question 312 pts
A new type of orange has been developed to be bigger than thetypical orange, which average 8 oz in weight. The critical Z valuefor a hypothesis test is 1.28 and the standard error is 2 oz. Whatis the minimum weight (in oz) of the sample of new oranges to yielda significant test result?
Group of answer choices
10.56+
13.88+
9+
5.04+
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Question 322 pts
A study was conducted on the effects of praise on children'sschool grades. If the study has high statistical power, it meansthat the probability is high for ____________.
Group of answer choices
getting a significant test result when praise actually has thepredicted effect on grades
not getting a significant result when praise does not actuallyhave the predicted effect on grades
getting a significant test result even when praise does notnecessarily have the predicted effect on grades
not getting a significant test result even when praise actuallyhas the predicted effect on grades
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Question 332 pts
A market researcher wants to know if Toyota vehicles havesignificantly higher MPGs compared to the national statistics. Shesets the α (significance) level at .10 for a one-tailed test. The Zstatistic calculated from the Toyota sample is 1.62. What is theconclusion from this hypothesis test?
Group of answer choices
The null hypothesis is rejected and Toyota vehicles havesignificantly higher MPGs compared to the national data.
The null hypothesis is rejected and Toyota vehicles do not havesignificantly higher MPGs compared to the national data.
The null hypothesis is not rejected and Toyota vehicles havesignificantly higher MPGs compared to the national data.
The null hypothesis is not rejected and Toyota vehicles do nothave significantly higher MPGs compared to the national data.
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Question 342 pts
What is a a sampling distribution?
Group of answer choices
It is a distribution of the means of all possible samples (of aparticular size) drawn from a population.
It has a mean and standard deviation which are are smaller thanthose of the original population from which it is derived.
It has a larger variability compared to the original populationfrom which it is derived.
It is composed of Z scores converted from the original scores inthe population.
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Question 352 pts
Compared to a sampling distribution with a mean of 100 and astandard error of 20, what is the Z statistic for the sample thatconsists of 98, 102, 108, 112.
Group of answer choices
.25
2.5
-.25
-2.5
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Question 362 pts
A teacher conducted a study to see if the students in his schoolperformed significantly worse than the national average on astandardized math test. He calculated the Z statistic to be -1.78while the critical value for the hypothesis test was -1.645. Hewould conclude that ___.
Group of answer choices
the null hypothesis was rejected and the students in his schoolperformed significantly worse than the national average.
the null hypothesis was rejected and the students in his schooldid not perform significantly worse than the national average.
the null hypothesis could not be rejected and the students inhis school pefromed significantly worse than the nationalaverage.
the null hypothesis could not be rejected and the students inhis school did not perform significantly worse than the nationalaverage.
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Question 372 pts
The average weight of 49 young males is 170 lbs. This sample iscompared to the general population of males in the same age range.The general population mean is 173 lbs and the standard deviationis 5 lbs. What is the standardized effect size of this test?
Group of answer choices
-0.60
.5
.3
3
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Question 382 pts
In a study on work hours, a sample of ASU psychology onlinestudents are compared to the general population of ASU onlinestudents and the Z statistic for the sample is -1.68. With aone-tailed test with an alpha level of .05, what is the conclusionof the hypothesis test?
Group of answer choices
Fail to reject the null hypothesis.
Reject the null hypothesis.
Reject the alternative hypothesis.
Reject both the null and the alternative hypotheses.
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Question 392 pts
What is the purpose of finding the standardized effect size of astudy?
Group of answer choices
To evaluate the practical importance of a result
To double check the test statistic for accuracy
To evaluate the null hypothsis
To see if the hypothesis test is significant or not
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Question 402 pts
What is the term for the standard deviation of the distributionof means (the sampling distribution)?
Group of answer choices
standard error
standard deviation
standard variance
shared variance
