Deck 10: Introduction to Hypothesis Testing

Question 1

What does alpha always represent in statistical hypothesis testing?

A)The probability of making a correct decision about
B)The relative size of the region of rejection
C)The critical value
D)0.05

Answer 1

The relative size of the region of rejection

Question 2

Which of the following is correct regarding experimental hypotheses?

A)We can prove that a predicted relationship exists in a population by confirming an experimental hypothesis.
B)They describe the population parameters that will be tested by the experiment.
C)They describe the predicted relationship we may or may not find in an experiment.
D)We can prove theories about behavior by confirming experimental hypotheses.

Answer 2

They describe the predicted relationship we may or may not find in an experiment.

Question 3

The null hypothesis describes the

A)sample statistic and the region of rejection.
B)sample statistic if a relationship does not exist in the sample.
C)population parameters represented by the sample data if the predicted relationship exists.
D)population parameters represented by the sample data if the predicted relationship does not exist.

Answer 3

population parameters represented by the sample data if the predicted relationship does not exist.

Question 4

When can the z-test be used in statistical hypothesis testing?

A)When the measure of central tendency used for the raw scores is the median
B)When the raw scores are transformed from a nominal scale to a ratio scale
C)When the raw score population's standard deviation is known
D)When the z-test standard deviation is known

Question 5

Which of the following alternative hypotheses would require using a two-tailed test?

A)
B)
C)
D)

Question 6

Why do we perform inferential statistics?

A)Because we know our sample is not representative.
B)Because it is possible we are being misled by sampling error.
C)Because we want to describe the characteristics of the population.
D)Because we need to be certain we make the correct decision.

Question 7

The key difference between parametric and nonparametric procedures is that parametric procedures

A)do not require that stringent assumptions be met.
B)require that certain assumptions be met.
C)are used for population distributions that are skewed.
D)are used for population distributions that have nominal scores.

Question 8

Which of the following is true of any one-sample experiment?

A)We must know the population mean under the same condition of the independent variable as the one being tested.
B)We must know the population mean under some condition of the independent variable other than the one being tested.
C)We must know the sample mean under the condition of the independent variable being tested,but we do not need to know the population mean.
D)We must know the sample mean under the condition of the independent variable being tested and under some other condition of the independent variable.

Question 9

If a sample mean is different from a particular population µ,we can conclude that the sample mean probably represents some other population or that

A)the sample mean does not represent the sample statistic.
B)an error was made in calculating the sample mean.
C)an error was made in calculating standard error.
D)the sample mean occurred as a result of sampling error.

Question 10

When is a one-tailed test used?

A)When no relationship is predicted
B)When a relationship is predicted and the direction in which the scores will change is predicted
C)When the demonstrated relationship is predicted
D)When a relationship is predicted without stating the direction in which the scores will change

Question 11

Which of the following is correct regarding statistical hypotheses (null hypothesis and alternative hypothesis)?

A)They describe the population parameters our sample data represent if the predicted relationship does or does not exist.
B)They describe the sample data if there is or is not a relationship in the population.
C)We can prove that a relationship exists in the population by confirming these hypotheses.
D)They are the hypotheses that we perform on the statistics in our experiment.

Question 12

When is a two-tailed test used?

A)When no relationship is predicted
B)When a relationship is predicted and the direction in which the scores will change is predicted
C)When the demonstrated relationship is predicted
D)When a relationship is predicted without stating the direction in which the scores will change

Question 13

For a two-tailed test where $\alpha$ = 0.05, is always equal to

A)-1.96.
B)+1.96.
C)±1.96.
D)±1.645.

Question 14

Which of the following is called the hypothesis of "no difference"?

A)The null hypothesis
B)The experimental hypothesis
C)The alternative hypothesis
D)The statistical hypothesis

Question 15

Which of the following null hypotheses would require using a two-tailed test?

A)
B)
C)
D)

Question 16

According to the null hypothesis,if our appears to represent the predicted relationship,it is because

A)the relationship actually exists.
B)our sample is invalid.
C)something has gone terribly wrong.
D)of sampling error.

Question 17

Which of the following is correct regarding alternative hypotheses?

A)They are alternatives to the experimental hypotheses.
B)They state the predicted relationship if the sample statistic does not fall in the region of rejection.
C)They describe the population parameters represented by the sample data if the predicted relationship exists.
D)They describe the population parameters represented by the sample data if the predicted relationship does not exist.

Question 18

Which of the following describe(s)the situation if the relationship you are testing in your experiment really exists?

A)The null hypothesis
B)The statistical hypotheses
C)The real-world hypothesis
D)The alternative hypothesis

Question 19

Which of the following assumptions is common to all parametric statistics?

A)There are no common assumptions.
B)The population of dependent scores,regardless of what kind of scores they are,forms a normal distribution.
C)The dependent scores must be interval or ratio scores,regardless of whether the population of scores forms a normal distribution.
D)The population of dependent scores,which must be interval or ratio scores,forms a normal distribution.

Question 20

Inferential statistics are used to

A)decide whether sample data accurately represent a particular relationship in the population.
B)get rid of sampling error.
C)improve sampling error.
D)decide whether the population causes a particular relationship in the sample data.

Question 21

For and ,what is the appropriate outcome of a z-test?

A) Reject .
B) Reject .
C) Reject .
D) Fail to reject .

Question 22

Which of the following statements does not belong?

A)We believe the relationship we found in our experiment represents a real relationship in the population.
B)The change in the dependent scores was produced by significant sampling error.
C)We obtained a significant z.
D)There is a significant effect of the condition.

Question 23

Suppose you conduct an experiment and the is statistically nonsignificant at -0.65.How would you correctly interpret this result?

A)
B)
C)
D)

Question 24

If and ,what is the value of ?

A)2.31
B)-1.30
C)-0.38
D)-2.31

Question 25

The population mean for the Elementary Tenacity Test (ETT)is 150,with .A recent study of elementary school children participating in a school lunch program obtained the following ETT scores.Use a two-tailed z-test and . 145 180 176 152 148 142 179 163 159 154
167 172 146 169 157 150 161 160 153 165

A) Fail to reject .
B) Reject and accept
.
C) Fail to reject .
D) Reject and accept
.

Question 26

If and what is the value of ?

A)2.58
B)0.52
C)-2.58
D)0.78

Question 27

Suppose you conduct an experiment and your is statistically significant at +3.45.How would you correctly interpret this result?

A)
B)
C)
D)

Question 28

Which of the following statements is true when is not rejected?

A)The experiment worked.
B)The data reflect a relationship found in nature.
C)The data do not provide sufficient evidence of a relationship in nature.
D)The data prove that the manipulation did not work.

Question 29

When statisticians report that the results from an experiment are significant,this means the results

A)are scientifically important.
B)are too unlikely to accept as sampling error.
C)differ from what was predicted by the experimental hypotheses.
D)do not differ from what was predicted by the null hypothesis.

Question 30

For and ,what is the appropriate outcome of a z-test?

A) Fail to reject .
B) Reject and accept
.
C) Reject and accept
.
D) Fail to reject .

Question 31

For and ,what is the appropriate outcome of a z-test?

A) Reject and accept
.
B) Reject and accept
.
C) Reject and accept
.
D) Fail to reject .

Question 32

When experimental results are significant,this means that the ______ hypothesis has been ______.

A)experimental;rejected
B)alternative;rejected
C)null;accepted
D)null;rejected

Question 33

What does the sampling distribution describe?

A)The sample distribution when the null hypothesis is true.
B)The sampling distribution when the null hypothesis is true.
C)The population distribution when the null hypothesis is false.
D)The alternative distribution when the null hypothesis is false.

Question 34

If and what is the value of ?

A)0.20
B)5.00
C)0.60
D)1.00

Question 35

In using a sampling distribution of means for statistical hypothesis testing,the mean of the sampling distribution will always equal

A)the µ described by .
B)the µ described by .
C)the sample mean.
D)0.0.

Question 36

For and ,what is the appropriate outcome of a z-test?

A) Reject and accept
.
B) Reject and accept
.
C) Reject and accept
.
D) Fail to reject .

Question 37

Suppose you have randomly selected high school students to take a course to improve their SAT scores.You find that the mean of their subsequent SAT scores is not significantly different from the population mean of SAT scores for those students who have not taken the course.Which of the following statements is the most appropriate conclusion?

A)We have proven that the course does not affect SAT scores.
B)We have obtained evidence consistent with the notion that the course has an effect on SAT scores.
C)We have obtained no convincing evidence that the course affects SAT scores.
D)The evidence suggests that the course may have an effect on SAT scores.

Question 38

When statisticians report that results are nonsignificant,the results are

A)not due to chance.
B)not important.
C)likely to reflect chance.
D)different from what was expected or predicted.

Question 39

What happens when the experimental results are nonsignificant?

A)The alternative hypothesis has been accepted.
B)The alternative hypothesis has been rejected.
C)The null hypothesis has been rejected.
D)The null hypothesis has not been rejected.

Question 40

Jeri has conducted a study on the average salary of recent graduates in her major at State College.She has randomly selected and surveyed 25 recent graduates from her program.The annual average income of this sample of recent graduates is $34,000.Jeri knows that the population mean income for recent graduates in her area of study is $31,000 with a If she uses and a two-tailed test,what is her conclusion?

A) Reject and accept
.
B) Reject and accept
.
C) Reject and accept
.
D) Reject and accept
.

Question 41

What does it mean when a computer printout reads "p = 0.03"?

A)The falls in the extreme 3% of the sampling distribution and the probability of a Type I error is 0.03.
B)The falls in the extreme 3% of the sampling distribution and the probability of a Type II error is 0.03.
C)The probability of a Type I error (0.03)is smaller than $\alpha$ (0.05),and,therefore,the results are nonsignificant.
D)The probability of an error should be reported as p $\lt$ 0.01.

Question 42

The power of a statistical test is the probability of

A)failing to reject a false .
B)failing to reject a true .
C)rejecting a false .
D)rejecting a true .

Question 43

In a one-tailed test is significant only if it lies

A)nearer than
and has a different sign from
.
B)in the tail of the distribution beyond and has a different sign from
.
C)nearer than
and has the same sign as
.
D)in the tail of the distribution beyond and has the same sign as
.

Question 44

Which of the following is the probability of avoiding a Type I error?

A)p = $\alpha$
B)p = (1- $\alpha$ )
C)p < $\alpha$
D)p > $\alpha$

Question 45

Which of the following tests is considered to be more powerful?

A)A one-tailed test
B)A two-tailed test
C)Neither;they are both equally statistically powerful
D)Which is more powerful depends on the sample size

Question 46

What happens to the probability of committing a Type I error if the level of significance is changed from $\alpha$ = 0.01 to $\alpha$ = 0.05?

A)The probability of committing a Type I error will decrease.
B)The probability of committing a Type I error will increase.
C)The probability of committing a Type I error will remain the same.
D)The change in probability will depend on your sample size.

Question 47

If you reject the null hypothesis,which of the following may occur?

A)A correct decision or a Type I error
B)A Type I error or a Type II error
C)A correct decision or a Type II error
D)A correct decision or a Type I error or a Type II error

Question 48

Which of the following represents a Type I error? We say that something

A)works when it really does.
B)works when it really doesn't.
C)doesn't work when it really does.
D)doesn't work when it really doesn't.

Question 49

The Physical Fitness Test (National Level for Girls)shows the national average for 10-year-old girls on "right-angle push-ups" to be = 13.Principal Smyth hypothesizes that her girls at Strong School are significantly above the national mean.If the and the scores for nine girls are as reported here,compute and determine if Principal Smyth is right.Use . 14 16 18 16 12 16 17 20 15

A) ,so Principal Smyth is right.
B) ,so Principal Smyth is wrong.
C) ,so Principal Smyth is right.
D) ,so Principal Smyth is wrong.

Question 50

To determine whether a new drug that is supposed to lower a person's heart rate is effective or not,Dr.Johnson gives the medicine to a random sample of 100 patients with rapid heart rhythm (RHR)and obtains a sample mean of 128.Dr.Johnson knows that the heart rate of the population of individuals with RHR is 135,with .If Dr.Johnson uses a one-tailed test and ,what is the appropriate conclusion?

A) Fail to reject .
B) Fail to reject .
C) Fail to reject .
D) Reject and accept
.

Question 51

Suppose that a population is known to have a mean of 80.If a researcher predicts the experimental treatment will produce an increase in the population mean,then the null hypothesis for this statistical hypothesis test would state

A)µ > 80
B)µ $\ge$ 80
C)µ $\le$ 80
D)µ < 80

Question 52

When choosing between one-tailed and two-tailed tests,

A)use a one-tailed test only if you have a convincing reason for predicting the direction.
B)always use two-tailed tests.
C)use a two-tailed test only if you have a convincing reason for not predicting a direction.
D)use the one that is most likely to produce significant results.

Question 53

Which of the following accurately defines a Type II error?

A)Rejecting when it is true
B)Rejecting when it is false
C)Failing to reject when it is true
D)Failing to reject when it is false

Question 54

Which of the following accurately defines a Type I error?

A)Rejecting when
is true
B)Rejecting when
is false
C)Retaining when
is true
D)Retaining when
is false

Question 55

Which of the following is correct regarding the probability of making a Type I error?

A)p = $\alpha$
B)p = (1 - $\alpha$ )
C)p < $\alpha$
D)p > $\alpha$

Question 56

For a one-tailed test where the predicted value of the sample mean is larger than the population mean and $\alpha$ = 0.05, is always equal to

A)±1.645.
B)+1.645.
C)-1.645.
D)±1.96.