Deck 7: Probability and Hypothesis Testing

Question 1

Given that on one section of the SAT the mean is 500 and the standard deviation is 100,what is the approximate probability of a student scoring 600 or higher on the test? a .84
B).50
C).16
D).34

Answer 1

C

Question 2

What is the probability of drawing either a king or a queen from a standard (52-card)deck of playing cards?

A).15
B).31
C).50
D).62

Answer 2

A

Question 3

What is the probability of rolling a 3 in a single roll of a die?

A).50
B)1.0
C).25
D).17

Answer 3

D

Question 4

What is the probability of pulling a jack from a standard (52-card)deck of playing cards?

A).019
B).077
C).15
D).25

Question 5

What it the probability of two heads in two flips of a coin?

A).25
B).50
C).75
D)1.0

Question 6

What is the probability of a couple having two children in the following order: girl,boy?

A).0625
B).125
C).25
D).50

Question 7

What is the probability of three tails in three flips of a coin?

A).25
B).75
C).125
D).50

Question 8

What is the probability of pulling a heart from a standard (52-card)deck of playing cards?

A).25
B).50
C).75
D)1.0

Question 9

What is the probability of a couple having three children in the following order: girl,girl,girl?

A).0625
B).125
C).25
D).50

Question 10

What is the probability of rolling an even number in a single roll of a die?

A).25
B).17
C).50
D).36

Question 11

What is the probability of drawing either a club or a spade from a standard (52-card)deck of playing cards?

A).25
B).50
C).75
D)1.0

Question 12

What is the probability of getting a 'head' on a single toss of a coin?

A)1.0
B)2.0
C).50
D).25

Question 13

Given that on one section of the SAT the mean is 500 and the standard deviation is 100,what is the approximate probability of a student scoring 400 or lower on the test? a .84
B).50
C).16
D).34

Question 14

What is the probability of a couple having four children in the following order: girl,girl,girl,boy?

A).0625
B).125
C).25
D).50

Question 15

What is the probability of a couple having either a girl or a boy when giving birth?

A).25
B).50
C).75
D)1.0

Question 16

Imagine that you have a bag filled with 10 pink marbles and 5 black marbles.What is the probability of pulling a pink marble from the bag?

A).25
B).33
C).50
D).67

Question 17

Imagine that you have a bag filled with 10 pink marbles and 5 black marbles.What is the probability of pulling a black marble from the bag?

A).25
B).33
C).50
D).67

Question 18

Probability is

A)the study of likelihood and uncertainty.
B)the number of ways a particular outcome can occur divided by the total number of outcomes.
C)the process of determining whether a hypothesis is supported by the results of a research study.
D)both the study of likelihood and uncertainty and the number of ways a particular outcome can occur divided by the total number of outcomes.

Question 19

What is the probability of rolling a two-digit number in a single roll of a die?

A)0
B)1.0
C).50
D).25

Question 20

Given that on one section of the SAT the mean is 500 and the standard deviation is 100,what is the approximate probability of a student scoring 400 or higher on the test? a .84
B).50
C).16
D).34

Question 21

Given that on one section of the SAT the mean is 500 and the standard deviation is 100,what is the approximate probability of selecting a student whose score is 400 or lower followed by selecting a student whose score is 500 or higher on the test? a .005
B).022
C).045
D).08

Question 22

H₀ is to H_a as _____ hypothesis is to _____ hypothesis.

A)null; alternative
B)alternative; null
C)one-tailed; two-tailed
D)two-tailed; one-tailed

Question 23

Given that on one section of the SAT the mean is 500 and the standard deviation is 100,what is the approximate probability of a student scoring 700 or higher on the test? a .98
B).02
C).12
D).75

Question 24

Given that on one section of the SAT the mean is 500 and the standard deviation is 100,what is the approximate probability of a student scoring 300 or lower or 700 or higher on the test? a .124
B).022
C).045
D).245

Question 25

Directional hypothesis is to non-directional hypothesis as _____ hypothesis is to _____ hypothesis.

A)null; alternative
B)alternative; null
C)one-tailed; two-tailed
D)two-tailed; one-tailed

Question 26

When using a _____ hypothesis the researcher predicts the direction of the expected difference between the groups.

A)null
B)non-directional
C)one-tailed
D)two-tailed

Question 27

In a study of the effects of exercise on stress,researchers predict simply that there will be a difference in stress level between the exercise and no exercise groups.The researchers are using a _____ hypothesis.

A)two-tailed
B)directional
C)one-tailed
D)one-tailed and directional

Question 28

One- and two-tailed hypotheses are both types of _____ hypotheses.

A)null
B)alternative
C)directional
D)non-directional

Question 29

Given that on one section of the SAT the mean is 500 and the standard deviation is 100,what is the approximate probability of selecting a student whose score is 400 or lower followed by selecting a student whose score is 600 or higher on the test? a .0005
B).002
C).025
D).045

Question 30

Given that on one section of the SAT the mean is 500 and the standard deviation is 100,what is the approximate probability of selecting a student whose score is 300 or lower followed by selecting a student whose score is 700 or higher on the test? a .0005
B).002
C).022
D).045

Question 31

No effect is to _____ hypothesis as effect is to _____ hypothesis.

A)null; alternative
B)alternative; null
C)one-tailed; two-tailed
D)two-tailed; one-tailed

Question 32

Given that on one section of the SAT the mean is 500 and the standard deviation is 100,what is the approximate probability of a student scoring 300 or higher on the test? a .98
B).02
C).12
D).75

Question 33

A liberal statistical test is one that

A)minimizes both type I and type II errors.
B)minimizes type I errors but increases type II errors.
C)minimizes type II errors but increases type I errors.
D)decreases the chance of type I errors.

Question 34

Given that on one section of the SAT the mean is 500 and the standard deviation is 100,what is the approximate probability of a student scoring 400 or lower or 500 or higher on the test? a .12
B).22
C).45
D).66

Question 35

The hypothesis predicting that differences exist between the groups being compared is to the hypothesis predicting that no differences exist between the groups being compared as _____ hypothesis is to _____ hypothesis.

A)null; alternative
B)alternative; null
C)one-tailed; two-tailed
D)two-tailed; one-tailed

Question 36

Given that on one section of the SAT the mean is 500 and the standard deviation is 100,what is the approximate probability of a student scoring 400 or lower or 700 or higher on the test? a .12
B).18
C).45
D).24

Question 37

When using a _____ hypothesis the researcher predicts that the groups being compared will differ,but does not predict how they will differ.

A)null
B)directional
C)one-tailed
D)two-tailed

Question 38

Inferential statistics allow us to

A)infer something about the sample based on the population.
B)infer something about the population based on the sample.
C)infer that the sample is representative.
D)all of the options are correct

Question 39

In a study on the effects of amount of sleep on driving performance,researchers predict that those in the group that is allowed more sleep will exhibit better driving performance.The researchers are using a _____ hypothesis.

A)two-tailed
B)directional
C)one-tailed
D)one-tailed and directional

Question 40

_____ statistics are used in the process of hypothesis testing.

A)Descriptive
B)Null
C)Alternative
D)Inferential

Question 41

Identify when it would be appropriate to use a parametric versus a nonparametric test.

Question 42

If weight in the general population is normally distributed with an average of 160 pounds and a standard deviation of 20 pounds what is the probability of selecting someone who weighs 170 or more pounds?

Question 43

If researchers report that the results from their study were significant,p < .05,this means that

A)if they conducted the study over they would get the same results less than 5 times in 100.
B)the results are untrustworthy.
C)we would expect the results to occur by chance less than 95 times out of 100.
D)we would expect the results to occur by chance less than 5 times out of 100.

Question 44

Explain how a one-tailed hypothesis differs from a two-tailed hypothesis.

Question 45

_____ are most often used with interval or ratio data whereas _____ are most often used with ordinal or nominal data.

A)t-tests; z-tests
B)z-tests; t-tests
C)Parametric tests; nonparametric tests
D)Nonparametric tests; parametric tests

Question 46

If weight in the general population is normally distributed with an average of 160 pounds and a standard deviation of 20 pounds what is the probability of selecting someone who weighs 120 or less pounds?

Question 47

Imagine that I have a jar that contains 20 black poker chips and 40 red poker chips.What is the probability of selecting a red poker chip followed by a black poker chip?

Question 48

A false alarm is to a(n)_____ as a miss is to a(n)_____.

A)Type I error; Type II error
B)Type II error; Type I error
C)null hypothesis; alternative hypothesis
D)alternative hypothesis; null hypothesis

Question 49

Imagine that I have a jar that contains20 black poker chips and 40 red poker chips.What is the probability of selecting a red poker chip or a black poker chip?

Question 50

Imagine that I have a jar that contains 20 black poker chips and 40 red poker chips.What is the probability of selecting a black poker chip?

Question 51

Imagine that I have a jar that contains20 black poker chips and 40 red poker chips.What is the probability of selecting a red poker chip?

Question 52

If weight in the general population is normally distributed with an average of 160 pounds and a standard deviation of 20 pounds what is the probability of selecting someone who weighs 120 or less or 170 or more pounds?

Question 53

Explain how Type I and Type II errors are related to false alarms and misses.

Question 54

If a researcher decides to use the .01 level of significance rather than using the more conventional .05 level of significance,what type of error is more likely to be made? Why?

Question 55

In a recent study,researchers concluded that exercise significantly lowered stress levels.What the researchers were unaware of,however,was that several of the participants in the exercise group were also taking anti-anxiety medications.The researchers' conclusion is a(n)_____ error.

A)Type II
B)Type I
C)null hypothesis
D)alternative hypothesis

Question 56

A researcher hypothesizes that children who learn to read using phonics will read better than those not taught in this manner.Identify H₀ and H_a.Is this a one- or two-tailed test?

Question 57

When the probability of a Type I error is .05 or less,we say that we have observed _____.

A)a Type II error
B)statistical significance
C)the alternative hypothesis
D)all of the above

Question 58

Rejecting H₀ when we should have failed to reject it is a _____ error.

A)Type I
B)Type II
C)null
D)one-tailed

Question 59

Failing to reject H₀ when we should have rejected it is a _____ error.

A)Type I
B)Type II
C)null
D)one-tailed

Question 60

Explain the difference between the null hypothesis and the alternative hypothesis in a study.

Question 61

What are inferential statistics and how do they differ from descriptive statistics?