Stats

The t distribution is the same for all sample sizes.

False

The t test for single samples is used when the population parameter µ is unknown.

False

The variance is the square of the standard deviation.

False

True or False: A significant Fobt value indicates that all the group means are significantly different from each other.

False

True or False: Correlation implies causation.

False

True or False: Fobt = MSwithin/MSbetween

False

True or False: If Fobt < Fcrit, we reject H0.

False

True or False: If Fobt is significant, it is possible to tell which groups differ from which without further analysis.

False

True or False: If c2 is negative then H0 must be false.

False

True or False: In a single variable c2 experiment there are N - 1 degrees of freedom.

False

True or False: In general, the Kruskal-Wallis test is as powerful as parametric ANOVA.

False

True or False: Nonparametric tests are generally more powerful than parametric tests.

False

True or False: Parametric tests are always more desirable than nonparametric tests.

False

True or False: The alternative hypothesis in an ANOVA can be either directional or nondirectional.

False

True or False: for the population 2, 4, 6, 8, 10... ux = 10/square root of 5

False

A scatter plot is a _________.

graph of paired X and Y values

A two-way ANOVA has _____ and a three-way ANOVA has _____.

two independent variables; three independent variables

The symbol SS stands for sum of squares.

True

The t distribution is a family of curves that vary with the degrees of freedom.

True

To use the z test, µ and σ must be known.

True

True or False: A value of -1.0 for Fobt is never possible if the calculations are done correctly.

True

True or False: An assumption of c2 is that the scores in each cell are independent.

True

True or False: Fobt = (SSbetween/dfbetween)/(SSwithin/dfwithin)

True

True or False: For a sample to be random, all the members must have an equal chance of being selected into the sample.

True

True or False: If F < 1, the independent variable has not had a significant effect.

True

True or False: If F < 1.0 we don't even have to bother to look up Fcrit since the result cannot possibly be significant.

True

True or False: In a 2 x 2 table there are (r - 1)(c - 1) degrees of freedom.

True

True or False: In general, nonparametric tests have fewer requirements or assumptions about population characteristics than parametric tests do.

True

True or False: SStotal = SSwithin + SSbetween

True

True or False: The F distribution has no negative values.

True

True or False: The area beyond a z score of +2.58 is 0.005.

True

True or False: The area beyond a z score of -1.12 is the same as the area beyond a z score of 1.12.

True

True or False: The t test for correlated groups is just like the t test for single samples except that it analyzes difference scores.

True

True or False: c2 is basically a measure of the overall discrepancy between fe and fo.

True

True or False: c2obt cannot be negative.

True

z scores allow comparison of variables that are measured on different scales.

True

For any distribution of scores ∑(X - µ) = _________.

0

Probabilities vary between _________.

0 and 1

The median is most affected by unbalanced extreme scores.

False

Given the following set of sample raw scores, X: 1, 3, 4, 6, 8. What is the z transformed value for the raw score of 3?

-0.52

A school psychologist is interested in determining if children with attention deficit disorder (ADD) learn better if English literature is read to them rather than having them read the material themselves. A random sample of 10 sixth graders with ADD is selected and divided into two groups of 5 each. One of the groups has a story read to them (Listening Group) and the other reads the story themselves (Reading Group). A quiz on the story is given after each group has finished reading or hearing the story. The following scores were obtained with 20 being a perfect score. Listening Group 10 10 10 12 8 Reading Group 8 8 10 12 7 the 95% confidence interval for µ1 - µ2 equals __________.

-1.54 - 3.54

Which of the following z scores represent(s) the most extreme value in a distribution of scores assuming they are normally distributed? A. 1.96 B. -3.12 C. 0.0001

-3.12

Suppose we measured the height of 1000 women and found that the data were normally distributed with a mean of 55.60 inches and a standard deviation of 3.05 inches. Suppose for the same 1000 women, we also measured their weight. Suppose the data were again normally distributed. The average weight is 165.60 lbs., and the standard deviation is 9.76 lbs. Suppose the correlation between height and weight is r = +.98. After using the regression equation to predict a person's weight who is 50 inches tall , you found out that that person is actually weighs 143 lbs, what is the residual? A. 2.05 B. -2.05 C. 5.02 D. -5.02

-5.02

The probability of throwing two ones with a pair of dice equals _________.

0.0278

The mean attention span for adults in a certain village is 15 minutes with a standard deviation of 6.4. What is the probability of randomly selecting a sample of 30 scores from this population that has a mean attention span equal to or greater than 17 minutes?

0.0436

If you have 15 red socks (individual, not pairs), 24 green socks, 17 blue socks, and 100 black socks, what is the probability you will reach in the drawer and randomly select a pair of green socks? (Assume sampling without replacement.)

0.3077

If µ = 400 and σ = 100 the probability of selecting at random a score less than or equal to 370 equals _________.

0.3821

The proportion of scores less than z = 0.00 is _________. (assume normal distribution)

0.50

A school psychologist is interested in determining if children with attention deficit disorder (ADD) learn better if English literature is read to them rather than having them read the material themselves. A random sample of 10 sixth graders with ADD is selected and divided into two groups of 5 each. One of the groups has a story read to them (Listening Group) and the other reads the story themselves (Reading Group). A quiz on the story is given after each group has finished reading or hearing the story. The following scores were obtained with 20 being a perfect score. Listening Group 10 10 10 12 8 Reading Group 8 8 10 12 7 The size of the effect, using Cohen's d equals _________.

0.58

A certain university maintains a colony of male mice for research purposes. The ages of the mice are normally distributed with a mean of 60 days and a standard deviation of 5.2. Assume you randomly sample one mouse from the colony. The probability his age will be between 55 and 70 days is _________.

0.8041

The standard deviation of the z distribution equals _________.

1

A factorial design has two levels of factor A and three levels of factor B with 6 subjects in each condition. The F-ratio for factor A would have _____ degrees of freedom.

1, 30

An economics test was given and the following sample scores were recorded: Individual A B C D E F G H I J Score 12 12 7 10 9 12 13 8 9 8 The z score for individual G is _________.

1.42

Five students were tested before and after taking a class to improve their study habits. They were given articles to read which contained a known number of facts in each story. After the story each student listed as many facts as he/she could recall. The following data was recorded. Before 10 12 14 16 12 After 15 14 17 18 20 Assume there is a real effect. using Cohen's d, the size of effect for the improvement, equals _________.

1.57

Is the difference between the mean preference scores of plain and sausage toppings significant?

1.7; not statistically significant

An economics test was given and the following sample scores were recorded: Individual A B C D E F G H I J Score 12 12 7 10 9 12 13 8 9 8 The mean of the distribution is _________.

10

An industrial psychologist observed 8 drill-press operators for one working day. She recorded the number of times each operator pressed the "faster" button instead of the "stop" button to determine whether the design of the control panel was contributing to the high rate of accidents in the plant. The resulting scores were as follows: 5, 2, 8, 2, 3, 2, 4, 12 The range for this distribution is _________.

10

A standardized test has a mean of 88 and a standard deviation of 12. What is the score at the 90th percentile? Assume a normal distribution.

103.36

A history professor gives a quiz to his class and records the following scores: 13, 11, 11, 9, 12, 13, 16, 14, 11, 10, 8, 13, 20. The mode(s) for this distribution is(are) _________.

11 and 13

A history professor gives a quiz to his class and records the following scores: 13, 11, 11, 9, 12, 13, 16, 14, 11, 10, 8, 13, 20. The range for this distribution is _________.

12

Source df SS MS F _____________________________________________________________________________ Subjects 7 15 Between 3 172 Error 21 98 Total 31 _____________________________________________________________________________ What is the value of F obtained?

12.28

A history professor gives a quiz to his class and records the following scores: 13, 11, 11, 9, 12, 13, 16, 14, 11, 10, 8, 13, 20. The mean for this distribution is _________.

12.38

An industrial psychologist observed 8 drill-press operators for one working day. She recorded the number of times each operator pressed the "faster" button instead of the "stop" button to determine whether the design of the control panel was contributing to the high rate of accidents in the plant. The resulting scores were as follows: 5, 2, 8, 2, 3, 2, 4, 12 The variance for this distribution is _________. Assume sample data.

12.79

Given the following set of scores X: 10, 12, 6, 8, 9, 11, 13, 13, 5, 0, 1 What is the mode?

13

Given the following set of scores X: 10, 12, 6, 8, 9, 11, 13, 13, 5, 0, 1 What is the range?

13

An industrial psychologist observed 8 drill-press operators for one working day. She recorded the number of times each operator pressed the "faster" button instead of the "stop" button to determine whether the design of the control panel was contributing to the high rate of accidents in the plant. The resulting scores were as follows: 5, 2, 8, 2, 3, 2, 4, 12 The mode for this distribution is _________.

2

A factorial design has two levels of factor A and three levels of factor B with 6 subjects in each condition. The F-ratio for the interaction of A x B would have _____ degrees of freedom.

2, 30

An economics test was given and the following sample scores were recorded: Individual A B C D E F G H I J Score 12 12 7 10 9 12 13 8 9 8 The standard deviation of the distribution is _________.

2.11

Given the following set of scores X: 10, 12, 6, 8, 9, 11, 13, 13, 5, 0, 1 What is the variance?

20.6

If a repeated measures ANOVA produced MSbetween = 20 and MSError = 5, then the F-ratio would be ________.

20/5 = 4

What proportion of pizza preference scores can be predicted by the pizza topping type?

29%

Is the difference between the mean preference scores of plain and pepperoni toppings significant?

2; not statistically significant

In a study with three levels of factor A, three levels of factor B, and 6 subjects in each condition, the dfs for factors A and B respectively would be _____ and _____.

2;2

If, in a repeated-measures ANOVA, k = 4 and n = 6, then the df for the F-ratio equals _________.

3, 15

ANOVA SUMMARY TABLE Source df SS MS F ____________________________________________________ Subjects 7 15 Between 3 172 Error 21 98 Total 31 __________________________________________________ What is the value of F critical for α=.05; based on this data should the null be rejected?

3.07; reject.

Suppose we measured the height of 1000 women and found that the data were normally distributed with a mean of 55.60 inches and a standard deviation of 3.05 inches. Suppose for the same 1000 women, we also measured their weight. Suppose the data were again normally distributed. The average weight is 165.60 lbs., and the standard deviation is 9.76 lbs. Suppose the correlation between height and weight is r = +.98. What is the slope of the best-fit line to predict weight from height? When height increases by one inch, how much does the predicted value of weight increase?

3.14 (to both)

An industrial psychologist observed 8 drill-press operators for one working day. She recorded the number of times each operator pressed the "faster" button instead of the "stop" button to determine whether the design of the control panel was contributing to the high rate of accidents in the plant. The resulting scores were as follows: 5, 2, 8, 2, 3, 2, 4, 12 The median for this distribution is _________.

3.50

Five students were tested before and after taking a class to improve their study habits. They were given articles to read which contained a known number of facts in each story. After the story each student listed as many facts as he/she could recall. The following data was recorded. Before 10 12 14 16 12 After 15 14 17 18 20 The obtained value of the appropriate statistic to evaluate H0 is _________.

3.51

An industrial psychologist observed 8 drill-press operators for one working day. She recorded the number of times each operator pressed the "faster" button instead of the "stop" button to determine whether the design of the control panel was contributing to the high rate of accidents in the plant. The resulting scores were as follows: 5, 2, 8, 2, 3, 2, 4, 12 The standard deviation for this distribution is _________. Assume sample data.

3.58

Assuming the z scores are normally distributed, what is the percentile rank of a z score of -0.47?

31.92

In a study with three levels of factor A, three levels of factor B, and 6 subjects in each condition, the df for the interaction of A x B would be ____

4

If the following scores were population scores X: 10, 12, 6, 8, 9, 11, 13, 13, 5, 0, 1 What would the standard deviation be?

4.33

If the population standard deviation is 19.0 and the sample size is 19, then the standard error equals _________.

4.36

An industrial psychologist observed 8 drill-press operators for one working day. She recorded the number of times each operator pressed the "faster" button instead of the "stop" button to determine whether the design of the control panel was contributing to the high rate of accidents in the plant. The resulting scores were as follows: 5, 2, 8, 2, 3, 2, 4, 12 The mean for this distribution is _________.

4.75

If a population of scores is normally distributed, has a mean of 45 and a standard deviation of 6, the most extreme 5% of the scores lie beyond the score(s) of _________. HINT: Each tail contains the most extreme 2.5% of the scores

56.76 & 33.24

A normally distributed set of population scores has a mean of 65 and a standard deviation of 10.2. The mean of the sampling distribution of the means for samples of size 48 equals _________.

65

In a normal distribution approximately _________ of the scores will fall within 1 standard deviation of the mean.

68%

In a two-way factorial ANOVA, the formula for calculating dfFactor A is

A - 1

Which Pearson correlation coefficient shows the strongest relationship between two variables? A. -0.80 B. 0.75 C. 0.20 D. 0.03

A. -0.80

A history professor gives a quiz to his class and records the following scores: 13, 11, 11, 9, 12, 13, 16, 14, 11, 10, 8, 13, 20. The median for this distribution is _________. A. 12 B. 11 C. 13

A. 12

The value of fe for the cell in row W, column A is _________. A B C W 16 25 64 X 28 32 30 Y 19 10 42 A. 24.9 B. 3.2 C. 63

A. 24.9

Prior to a recent gubernatorial election, a survey was conducted to determine whether there was a relationship between sexual gender and preference for the Democratic or Republican candidate. The following data were recorded. Assume the data will be analyzed with Chi-square. Republican Democrat Female 82 118 Male 68 132 _______________________________________________ 150 250 Using a = 0.05, c2crit = _________. A. 3.841 B. 5.412 C. 2.706 D. -3.8431

A. 3.841

There were 100 pirates on a ship. You were curious to know the average and variability of the gold coins that pirates have. You have sampled five of them and asked how many gold coins that they have and they answered as 2, 4, 5, 6 and 8. The mean is___ and the standard deviation is _______ A. 5 and 2.24 B. 4 and 3.24 C. 5 and 4.40 D. 4 and 3.40

A. 5 and 2.24

If SSwithin = 126, N = 28, k = 4, then what is the value of MSwithin? A. 5.25 B. 4.20 C. 4.667

A. 5.25

If a = 0.05, and df = 4, the value of c2crit = _________. A. 9.488 B. 0.711 C. 7.815 D. 11.070

A. 9.488

Classifying subjects on the basis of sex is an example of using what kind of scale? A. nominal B. ordinal C. interval

A. nominal

If a relationship is linear, _________. A. the relation can be most accurately represented by a straight line B. all the points fall on a curved line C. the relationship is best represented by a curved line D. all the points must fall on a straight line

A. the relation can be most accurately represented by a straight line

A math teacher has been teaching a sixth grade algebra class for many years. She has the feeling that over the past several years, math ability of students has changed. A national test of proficiency in algebra was administered 10 years ago. The resulting distribution of scores was normally shaped, had a mean of 55 and a standard deviation of 12. In order to test her feeling she gives her present class of 36 students the same proficiency test and she finds the average as 51. (Make your decision at the significance level of α = 0.01) The obtained value of the appropriate statistic for testing H0 is _________; and you decide to _________ A. 4; fail to reject the null B. -2; fail to reject the null C. -4; reject the null D. -2; reject the null

B. -2; fail to reject the null

A testing bureau reports that the mean for the population of Graduate Record Exam (GRE) scores is 500 with a standard deviation of 90. The scores are normally distributed. The proportion of scores that lie between 460 and 600 is _________. A. 0.4394 B. 0.5365 C. 0.4406 D. 0.4635

B. 0.5365

Prior to a recent gubernatorial election, a survey was conducted to determine whether there was a relationship between sexual gender and preference for the Democratic or Republican candidate. The following data were recorded. Assume the data will be analyzed with Chi-square. Republican Democrat Female 82 118 Male 68 132 _______________________________________________ 150 250 The value of df = _________. A. 2 B. 1 C. 3

B. 1

In an experiment using the independent groups design, there are 10 subjects in one group and 12 subjects in the other group. Degrees of freedom is equal to _____________ A. 22 B. 20 C. 10 D. 11

B. 20

A history professor gives a quiz to his class and records the following scores: 13, 11, 11, 9, 12, 13, 16, 14, 11, 10, 8, 13, 20. The standard deviation for this distribution is _________. Assume sample scores. A. 3 B. 3.12 C. 13.26 D. 13

B. 3.12

If a researcher reported an F-ratio with df = 3, 30 for a randomized ANOVA, then there were _____ conditions in the experiment and _____ total subjects. A. 3; 10 B. 4; 11 C. 4; 10 D. 3; 11

B. 4; 11

If SStotal = 20 and SSbetween = 14, SSwithin = _________. A. 34 B. 6 C. -6

B. 6

The value of c2obt for the table below is _________. (Assume equal probabilities for fe in each cell.) | 12 | 20 | 16 | 18 | 30 | A. 96 B. 9.42 C. 8.13 D. 13.28

B. 9.42

Which of the following statements concerning Pearson r is NOT true? A. r = 0.00 represents the absence of a relationship. B. The relationship between the two variables must be nonlinear. C. r = 0.76 has the same predictive power as r = -0.76. D. r = 1.00 represents a perfect relationship.

B. The relationship between the two variables must be nonlinear.

From which of the following studies can one most reasonably determine cause and effect? A. correlational study B. experimental study C. case study

B. experimental study

In a negatively skewed distribution, the mean will generally be _______ the median. A. greater than B. less than C. equal to

B. less than

The mean is _______ sensitive to extreme scores than the median. A. less B. more c. equally

B. more

Which of the following values of r represents the strongest degree of relationship between two variables? A. 0.55 B. 0.78 C. -0.80

C. -0.80

Y can be most accurately predicted from X if the correlation between X and Y is _________. A. 0.80 B. 0.45 C. -0.98

C. -0.98

If 49% of the total variability of Y is accounted for by X, what is the value of r? A. 0.49 B. 0.51 C. 0.70 D. 0.30

C. 0.70

Prior to a recent gubernatorial election, a survey was conducted to determine whether there was a relationship between sexual gender and preference for the Democratic or Republican candidate. The following data were recorded. Assume the data will be analyzed with Chi-square. Republican Democrat Female 82 118 Male 68 132 _______________________________________________ 150 250 The value of c2obt = _________. A. 2.06 B. 2.09 C. 1.80 D. 1.75

C. 1.80

If an experiment using frequency data tested the preference for 6 brands of soup, there would be _________ degrees of freedom. A. 1 B. N - 1 C. 5 D. 6

C. 5

The following ANOVA TABLE corresponds to an experiment with a within subject design on Pizza preference (0-10) based on topping (plain, sausage, pepperoni, or everything). The mean preference scores for each type of pizza topping as follows: Plain: 8.5 Sausage: 6.8 Pepperoni: 6.5 Everything: 2.7 ANOVA SUMMARY TABLE ____________________________________________________ Source df SS MS F ____________________________________________________ Subjects 7 112 16 Between __ 150 ___ ____ Error 21 250 11.90 Total 31 ____ ____________________________________________________ Is the difference between the mean preference scores of plain and everything toppings significant? A. 2; not statistically significant B. 3.02; statistically different C. 5.8; statistically different Correct D. 5.8; not statistically significant

C. 5.8; statistically different

A consulting psychologist is consulting with X-Bookstore to monitor customer complaints. The national average for all bookstores is 6 complaints per month. Nine branches of X-Bookstore have been randomly selected to determine whether X-Bookstore has a different average number of complaints than bookstores in general. The average number of complaints from these 9 branches of X-Bookstore was calculated as 5 with the standard deviation of 3. Using .05 level of significance, what should the psychologist conclude? A. Fail to reject the null; X-Bookstore has significantly higher complaints than bookstores in general B. Reject the null; X-Bookstore has significantly higher complaints than bookstores in general Incorrect C. Fail to reject the null; There is no significant difference between the complaints received from X-bookstore and bookstores in general D.. Reject the null; There is no significant difference between the complaints received from X-bookstore and bookstores in general

C. Fail to reject the null; There is no significant difference between the complaints received from X-bookstore and bookstores in general

Makaela took a Spanish exam; her grade was 79. The distribution was normally shaped with mc047-1.jpg= 70 and s = 12. Juan took a History exam; his grade was 86. The distribution was normally shaped with mc047-2.jpg= 80 and s = 8. Which did better on their exam relative to those taking the exam? A. Makaela B. Juan C. Neither, both did as well as each other.

C. Neither, both did as well as each other.

Suppose we measured the height of 1000 women and found that the data were normally distributed with a mean of 55.60 inches and a standard deviation of 3.05 inches. Suppose for the same 1000 women, we also measured their weight. Suppose the data were again normally distributed. The average weight is 165.60 lbs., and the standard deviation is 9.76 lbs. Suppose the correlation between height and weight is r = +.98. What is your best guess for the weight of a man who is 50 inches tall? A. about 130 lbs B. about 160 lbs C. about 148 lbs D. about 128 lbs

C. about 148 lbs

In most situations, parametric tests _________. A. have the same power as nonparametric tests B. are less powerful than nonparametric tests C. are more powerful than nonparametric tests

C. are more powerful than nonparametric tests

Correlation and regression differ in that _________. A. a. correlation is primarily concerned with the size and direction of relationships B.. regression is primarily used for prediction C. both of these are true D. neither of these are true

C. both of these are true

Let's assume that we have determined the salary of all the professors at your school. In plotting the distribution of salaries we notice that it is positively skewed. For this distribution __________. A. mean = median B. mean < median C. mean > median

C. mean > median

Prior to a recent gubernatorial election, a survey was conducted to determine whether there was a relationship between sexual gender and preference for the Democratic or Republican candidate. The following data were recorded. Assume the data will be analyzed with Chi-square. Republican Democrat Female 82 118 Male 68 132 _______________________________________________ 150 250 Using a = 0.05, what is your conclusion? A. accept H0; there is no relationship between sex and candidate preference B. reject H0; there is a significant relationship between sex and candidate preference C. retain H0; the study does not show a significant relationship between sex and candidate preference D. retain H0; this study shows a significant relationship between sex and candidate preference

C. retain H0; the study does not show a significant relationship between sex and candidate preference

In order to estimate the amount of TV watched by New York City adults, a sociologist surveys a random sample of adults from this city. The average (mean) of the raw scores is a _________. A. population B. sample C. statistic D. parameter

C. statistic

Suppose we measured the height of 1000 women and found that the data were normally distributed with a mean of 55.60 inches and a standard deviation of 3.05 inches. Suppose for the same 1000 women, we also measured their weight. Suppose the data were again normally distributed. The average weight is 165.60 lbs., and the standard deviation is 9.76 lbs. Suppose the correlation between height and weight is r = +.98. What is the intercept of the best-fit line to predict weight from height? A. -52.13 B. 8.98 C. 52.13 D. -8.98

D. -8.98

The lowest degree of correlation shown below is _________. A. 0.75 B. -0.33 C. -0.25 D. 0.15

D. 0.15

If, for a repeated measures ANOVA, F(2, 24) = 4.45, p < .05, how many subjects were there in the study? A. 25 B. 39 C. 24 D. 13

D. 13

Descriptive statistics are used to _________. A. calculate the mean and standard deviation of a sample B. calculate the mean and standard deviation of a population C. graph a distribution of raw scores D. all of these

D. all of these

In a normal distribution the z score for the mean equals _________. A. 0 B. the z score for the median C. the z score for the mode D. all of these

D. all of these

The sampling distribution of chi-square is _________. Select one: A. skewed B. varies with df C. is a theoretical distribution D. all of these

D. all of these

Which of the following are nonparametric tests? A. Wilcoxon test B. Mann-Whitney U test D. Kruskal-Wallis test D. all of these

D. all of these

Which of the following are true? A. fo is the symbol for the observed frequency B. fe is the symbol for the expected frequency C. c2 is the symbol for chi-square D. all of these

D. all of these

In an experimental study of the effects of practice on reaction time, reaction time would be the​... A. independent variable B. experimental group C. control group D. dependent variable

D. dependent variable

Which of the following increase(s) the power of the t test? A. decreasing N B. increasing the sample variance(s) C. decreasing the effect of the independent variable D. all of these E. increasing N and increasing the effect of the independent variable

E. increasing N and increasing the effect of the independent variable

Knowing nothing more than that IQ and memory scores are correlated 0.84, you could validly conclude that _________. A. good memory causes high IQ B. high IQ causes good memory C. neither good memory nor high IQ cause each other D. a third variable causes both good memory and high IQ E. none of these

E. none of these

Which of the following are examples of parametric tests? A. t test B. Mann-Whitney U test C. Chi-square test D. F test E. t test and F test

E. t test and F test

Which of the following are examples of nonparametric tests? A. one sample t and independent samples t test B. z test and F test C. Mann-Whitney U test and F test D. Chi-square test and one sample t test E. F test and Chi-square test F. Mann-Whitney U test and Chi-square test

F. Mann-Whitney U test and Chi-square test

A school psychologist is interested in determining if children with attention deficit disorder (ADD) learn better if English literature is read to them rather than having them read the material themselves. A random sample of 10 sixth graders with ADD is selected and divided into two groups of 5 each. One of the groups has a story read to them (Listening Group) and the other reads the story themselves (Reading Group). A quiz on the story is given after each group has finished reading or hearing the story. The following scores were obtained with 20 being a perfect score. Listening Group 10 10 10 12 8 Reading Group 8 8 10 12 7 What do you conclude, using a = 0.052 tail?

Fail to Reject Ho

If the raw score distribution is very positively skewed, the standard deviation of the z transformed scores will not equal 1. Select

False

In a skewed distribution, the mean and median are equal.

False

It is impossible to have a z score of 23.5.

False

Probability values range from -1.00 to +1.00.

False

When a sampled score is put back in the population before selecting the next score, this process is called sampling without replacement.

False

When calculating the population standard deviation, we use N - 1 in the denominator.

False

_____ statistics are used in the process of hypothesis testing.

Inferential

In a two-way factorial ANOVA, the final F ratio for Factor A×B is determined by dividing _____ by _____.

MSA×B; MSError

In a repeated-measures ANOVA, the final F ratio is determined by dividing _____ by _____.

MSBetween; MSError

In a two-way factorial ANOVA, the final F ratio for Factor A is determined by dividing _____ by _____.

MSFactor A; MSError

In a two-way factorial ANOVA, the final F ratio for Factor B is determined by dividing _____ by _____.

MSFactor B; MSError

If the distribution is symmetrical, which is the best measure of central tendency?

Mean

In a two-way factorial ANOVA, the formula for calculating dfTotal is

N-1

A distribution has a mean of 78 and a median of 92. This distribution is _________.

Negatively Skewed

If a distribution of raw scores is negatively skewed, transforming the raw scores into z scores will result in a _________ distribution.

Negatively Skewed

Concluding there is no effect of the independent variable is to the _____ hypothesis, as concluding there is an effect of the independent variable is to the _____ hypothesis.

Null; Alternative

H0 is to Ha as _____ hypothesis is to _____ hypothesis.

Null; Alternative

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

One-Tailed

In a positively skewed distribution, the mean has a higher value than the median.

True

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

Parametric Tests; nonparametric Tests

An English teacher has been teaching a sixth grade composition class for many years. He has the feeling that over the past several years, the writing ability of students has changed. A national test of proficiency in composition was administered 5 years ago. The resulting distribution of scores was normally shaped, had a mean of 85 and a standard deviation of 10.9. In order to test his feeling, he gives his present class of 43 students the same proficiency test. The resulting mean is 80 and the standard deviation is 8.7. Using the z test with a = 0.052 tail, what is your conclusion?

Reject H0; the present class appears deficient in composition writing

General State University recently decided to discontinue its use of the GRE as an admissions tool for its graduate programs because they observed no correlation between GRE scores and subsequent GPAs. Ninety percent of the grades awarded in the graduate programs at General State University are A's. What General State has failed to consider in this situation is the issue of​ __________________.

Restrictive Range

In a two-way factorial ANOVA, to calculate MSA×B we divide _____ by _____.

SSA×B; dfA×B

In a two-way factorial ANOVA, to calculate MSError we divide _____ by _____.

SSError; dfError

In a two-way factorial ANOVA, to calculate MSFactor A we divide _____ by _____.

SSFactor A; dfFactor A

Source df SS MS F ___________________________________________________________________________ A (Temp) 250 B (Time) 15 A x B 300 Within 300 Total ---------------------- If you fill in the ANOVA table, it would look like....

Source df SS MS F _____________________________________________________________________________ A (Temp) 2 250 125 22.48 B (Time) 1 15 15 2.70 A x B 2 300 150 26.98 Within 54 300 5.56 Total 59 _____________________________________

An observed difference between two descriptive statistics that is unlikely to have occurred by chance represents

Statistical Significance

The addition rule is concerned with determining the probability of A or B, while the multiplication rule is concerned with determining the probability A and B.

True

The degrees of freedom equal N - 1 for the t test for single samples.

True

The normal curve never touches the X axis.

True

The range is equal to the highest score minus the lowest score.

True

Table A in your textbook has no negative z values, this means _________.

The table can be used with both positive and negative z values because it is symmetrical Correct

Calculate Tukey HSD at α=.05, do the necessary pairwise comparisons and sketch a graph of the means. Based on the ANOVA table, Tukey HSD that you have calculated, pairwise comparisons and the graph, which one of the alternatives provide the summary of the results? Note: F critical with degrees of freedom (1,54) at alpha .05 is 4.02 and F critical with degrees of freedom (2,54) at alpha .05 is 3.17.

There is a significant main effect of Temperature, F (2, 54) = 22.48, p < .05. Workers were more productive in the cooler temperatures and productivity decreased as temperature increased. Based on Tukey's HSD, all comparisons for productivity scores across differing temperatures were significant at α= .05. There was no significant main effect of time of day. There was a significant interaction effect, F (2, 54) = 26.98, p < .05. In the afternoon, productivity was fairly constant across differing temperatures, however, in the morning, temperature made a large difference with respect to productivity with workers being more productive in cooler temperatures and less productive as temperatures increased.

20 students were given a 10 item quiz. Five students scored 6, six students scored 7 and nine students scored 10. If we randomly select a student from these 20 students, the probability that his/her quiz score is at least 6 is 1

True

A percentile rank is a score that indicates the percentage of people who scored at or below a given raw score.

True

If one uses N instead of N - 1 in the denominator of the equation for the sample standard deviation, one will underestimate the population standard deviation.

True

In decision making, when we make a false alarm it is similar to a _____ and when we make a miss it is similar to a _____.

Type I error; Type II error

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

Type II

Is there a significant effect of topping type on pizza preference scores?

Yes

In a two-way factorial ANOVA, the formula for calculating SSA×B is:

[Σ(XbarC -Xbar G)2nC] - SSA - SSB

In the equation Y = bX + a, a is _________.

a constant giving the value of the Y Axis intercept

In a repeated-measures ANOVA, the total variance is comprised of....

between-groups, error, and participant variance.

In a negative relationship, _________.

d. as X increases, Y decreases

In a repeated-measures design, the single largest contributing factor to error variance has been removed. What is that factor?

individual differences

When a correlation exists, lowering the range of either of the variables will _________.

lower the correlation

A liberal statistical test is one that

minimizes type II errors but increases type I errors.

The proportion of variance accounted for by a correlation between two variables is determined by _________.

r squared (coefficient of determination)

Five students were tested before and after taking a class to improve their study habits. They were given articles to read which contained a known number of facts in each story. After the story each student listed as many facts as he/she could recall. The following data was recorded. Before 10 12 14 16 12 After 15 14 17 18 20 What do you conclude using a = 0.05 2 tail?

reject H0; the class appeared to improve study habits

In inferential statistics the object is usually to generalize from a _________ to a _________.

sample; population

If a linear correlation is perfect, all the points must fall on a __________________

straight line

Which of the following is not an assumption of the one-way repeated measure ANOVA?

the groups are independent

In the equation Y = bX + a, b is _________.

the slope of the line

In the equation Y = bX + a, X and Y are _________.

variables

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

we would expect the results to occur by chance less than 5 times out of 100.

An English teacher has been teaching a sixth grade composition class for many years. He has the feeling that over the past several years, the writing ability of students has changed. A national test of proficiency in composition was administered 5 years ago. The resulting distribution of scores was normally shaped, had a mean of 85 and a standard deviation of 10.9. In order to test his feeling, he gives his present class of 43 students the same proficiency test. The resulting mean is 80 and the standard deviation is 8.7. The obtained value of the appropriate statistic for testing H0 is _________.

zobt = -3.01

In an independent groups design the nondirectional alternative hypothesis states _________.

µ1 ≠ µ2

In a two-way factorial ANOVA, the formula for calculating SSTotal is:

Σ(X-XbarG)2

In a two-way factorial ANOVA, the formula for calculating SSFactor A is:

Σ[(XbarA -XbarG)2nA]

In a two-way factorial ANOVA, the formula for calculating SSFactor B is:

Σ[(XbarB -XbarG)2nB]