Quantitative Measures Final

what z-scores corresponds to a score that is above the mean by 2 standard deviations?

+2.

For a population with μ =40 and σ = 8, what is the z-score corresponding to X = 34

-0.75

What is the value of SP for the following set of data? X: 4,1,1,2 Y:3,2,5,6

-1

What is the value of SP for the following set of data? X: 1,2,9 Y: 4,4,1

-15

A set of X and Y scores has a regression equation with a slope of b = 4. If the mean for the X values is Mx = 2 and the mean for the Y values is My = 6, wha is the Y-intercept vale for the regression equation?

-2

a random sample of n = 4 scores is obtained from a normal population with μ = 30 and σ = 8. What is the probability tht the sample men will be smaller than M = 22.

0.0228

What proportion of a normal distribution is located in the tail beyond z = 1.50?

0.0668

What proportion of a normal distribution is located in the tail end beyond z = -1.00?

0.1587

a normal distribution has a mean of μ =40 and σ = 10. If a vertical line is drawn through the distribution at X = 35, what proportion of the scores are left on the left side of the line?

0.3085

What proportion of a normal distribution is located between the mean and z = -1.40?

0.4192

A sample is selected from a population with μ = 46, and a treatment is administered to the sample. After treatment, the sample mean is M = 48 with a sample variance of s2 = 16. Based on this information, what is the value of cohen's d?

0.50

A sample of n = 9 individuals is selected from a population with μ = 60 and σ = 6, and a treatment is administered to the sample, After treatment, the sample mean is M = 63. What is the value of cohen's d for this sample?

0.50

A normal distribution has a mean of μ = 100 and σ = 20. If one score is randomly selected from this distribution, what is the probability that the score with have a value between X = 90 and X = 120?

0.5328

A random sample of n = 9 scores is selected from a normal distribution with μ = 80 and σ = 12. what is the probability that the sample mean will be between 76 and 84?

0.6426

a normal distribution has a mean of μ = 60 and σ = 8. if one score is randomly selected from this distribution, what is the probability that the score will be greater than X = 54?

0.7734

What proportion of a normal distribution is located between z = -1.25 and z = +1.25?

0.7888

A vertical line drawn through a normal distribution at z = -1.00 separated the distribution into to sections, the body and the tail. What proportion of the distribution isin the body?

0.8413

if an entire population with μ = 60 and σ = 8 is transformed into z-scores, then the distribution of z-scores will have a mean of ___ and a standard deviation of ___.

0;1

what is the variance for the following population of scores? Scores: 5,2,5,4

1.5

For the following distribution, what percentage of the individuals have scores of X = 1? X:5,4,3,2,1. f:2,8,5,3,2

10%

A class consist of 10 males and 30 females. A random sample of n = 3 students is selected. if the first two students are both females, what is the probability that the third student is male?

10/40

For the following data, N = ____. X: 4,3,2,1. f: 2,4,3,2

11

A sample of 100 people is classified by gender (male/female) and by whether or not they are registered voters The sample consists of 80 females and 20 males and has a total of 60 registered voters. if these data were used for a chi-square test for independence, what is the expected frequency for males who are registered voters

12

What is the value of SS (sum of squared deviations) for the following population?population: 1, 1, 1, 5

12

What is the value of the SS (sum of squared deviations) for the following population? population: 2, 3, 0, 5

13

Suppose the correlation between height and weight for adults is +0.40. What proportion (or percent) of the variability in weight can be explained by the relationship with height?

16%

A population of N = 100 scores has μ =30 and σ = 4. What is the population variance?

16.

What is the value of SS for the following set of scores? Scores: 0, 1, 4, 5

17

A researcher conducts a hypothesis test using a sample of n = 20 from an unknown population. What is the df value for the t statistic

19

A researcher is using a chi-square test for independence to evaluate the relationship between birth-order position and self esteem. Each individual is classifies as being 1st born 2nd bon, or 3rd born, and self esteem is categorized as either high or low For this study, what is the df values fro the chi-square statistic?

2

A sample of n = 9 scores has a varianc of s^2 = 36. What is the estimated standard error for the sample mean?

2

What is the median for the set of scores shown in the frequency distribution table? X: 5,4,3,2,1. f: 1,1,2,3,4

2

What is the mode for the population of scores shown in the frequency distribution table? X: 5,4,3,2,1. f: 1,2,3,4,2

2

For the linear equation Y = 2X + 4, if X increases by 1 point, how much will Y increase?

2 points

A sample of n = 16 scores produces a t statistic of t = 2.00.If he sample is used to measure effect size with r2, what value will be obtained for r2?

2/20

For the following data, what is the value of SSb? B1 B2 A1 [N=5,M=1,SS=10] [N=5,M=2,SS=20] A2 [N=5,M=1,SS=10] [N=5,M=4,SS=20]

20

The following data represents the means for each treatment condition in a two fatcor experiment. Note that one mean is not given. WHat value for the mssing mean would result in no AxB interaction? B1 B2 A1 20 30 A2 10 ?

20

A researcher selects a sample of 100 people to investigate the relationship between gender (male/female) and registering to vote, The sample consists of 40 females, of whom 30 are registered voters, and 60 males, of whom 40 re registered voters. If these data were used for a chi-square test for independence, what is the expected frequency for the registered females?

28

A chi-square test for goodness of fit has df = e. How many categories were used to classify the indiciduals in the sample?

3

A population of scores has μ = 80. In this population, a score of X=86 corresponds to z = +2.00. What is the population standard deviation?

3

a repeated measures study uses a sample of n = 15 participants to evaluate the mean differences among four treatments conditions. in the analysis of variance for this study, what is the value for df BETWEEN treatments

3

a sample of n=25 scores has a mean of M = 20 and s^2 = 9. What is the sample standard deviation?

3

A two factor study with two levels of factor A and three levels of factor B uses a separate group of n = 5 participants in each treatment condition. How many participants are needed for the entire study?

30

A set of n = 15 pairs of X and Y scores has SSx = 10, SSy = 40, and SP = 30. WHat is the slope for the regression equation for predicting Y from X?

30/10

What is the mean for the population of scores shown in the frequency distribution table? X: 5,4,3,2,1. f: 1,2,3,4,2

32/12

In a population with a standard deviation of σ = 5, a score of X = 44 corresponds to a z-score of z = 2.00. What is the population mean?

34

A sample of n = 4 scores is selected from a population with μ = 40 and σ = 8, and the sample mean if M=43. What is the standard error for the sample mean?

4

Ten years ago, only 20% of the U.S. population consisted of people more than 65 years old. A researcher plans to use a sample of n = 200 people to determine whether the population distribution has changed during the past ten years. If a chi-square test is used to evaluate the data, what is the expected frequency for the older-than-65 category?

40

A sample has a mean of M = 90. if each score in the sample is multiplied by 5, what is the mean for the new distribution?

450

A population of n = 8 scores has ΣX= 40. What is the population mean?

5

For the following distribution of quiz scores, if a score of X = 3 or higher is needed for a passing grade, how many individuals failed the quiz? X: 5,4,3,2,1. f: 6,5,5,3,2

5

a sample of n=36 scores is selected from a population with σ = 12. if the mean of M = 56 produces a z-score of z = +3.00, then what is the population mean?

50

For a population with μ =40 and σ = 8, what is the X value corresponding to z = 1.50?

52

For the following data, what is SS BETWEEN subject? A 3 4 5 12 b 1 1 2 6 c 2 1 6 9 t=6 t = 6 t = 15 SS = 2 SS = 6 SS = 2

6

Sample of size n = 9 are selected from a population with μ = 80 and σ = 18. What is the standard error for the distribution of sample means?

6

A set of n = 15 pairs of scores (X and Y values) has SSx = 4, SSy = 25, and SP = 6. What is the Pearson correlation for these data?

6/10

For the following data, what is the value of SS WITHIN? B1 B2 A1 [N=5,M=1,SS=10] [N=5,M=2,SS=20] A2 [N=5,M=1,SS=10] [N=5,M=4,SS=20]

60

After every score in a sample is multiplies by 3, he mean is calculated and found to be M = 21. What was the mean for the original scores?

7

For the following distribution, how many people have scores greater than X = 14? X: 20-24,15-19.10-14,5-9. f: 2,5,4,1,

7

a repeated measures ANOVA with n = 5 subject has df WITHIN treatment equal to 12. What is the value for df error for this analysis

8

For a population with μ = 80 and σ = 20, the distribution of sample means based on n = 16 will have and expected value of _____ and a standard error of _____.

80;5

Which of the following is a requirement for a random sample?

All of the other 3 choices are correct. (every individual has an equal chance, the prob. cannot change during a series, must be sampling replacement.)

A sample has a mean of M = 39.5 and a standard deviation of s = 4.3, and produces a t statistic of t = 2.13. For a two-tailed hypothesis test with alpha= .05, what is the correct statistical decision for this sample?

It is impossible to make a decision about h0 without more info.

A sample of n = 4 scores is obtained from a population with μ = 70 and σ = 8. If the sample mean corresponds to a z-score of 2.00, what is the value of the sample mean?

M=78

If a set of exam scores forms a negatively skewed distribution, what can you conclude about the students' scores?

Most of the students had relatively high scores.

A population with mean of μ = 6 has ΣX = 54. How many scores are in the population?

N = 9.

Which of the following accurately describes the critical region?

Outcomes with a very low probability if the null hypothesis is true

What is the shape of the distribution for the following set of data? X: 5,4,3,2,1. f: 1,1,2,4,5.

Positively skewed

What term is used to describe the shape of a distribution in which the scores pile up on the left-hand side of the graph and taper off to the right?

Positively skewed

a two-tailed hypothesis test is being used to evaluate a treatment effect with α = .05. if the sample data produce a z-score of z = -2.24, what is the correct decision?

Reject the null hypothesis and conclude that the treatment has an effect

The average verbal SAT score for the entire class of entering freshmen is 530. However, if you select a sample of 20 freshmen and compute their average SAT score you probably will not get exactly 530. What statistical concept is used to explain the natural difference that exists between a sample mean and the corresponding population mean

Sampling error

For the following scores, which of the following actions will increase the range? Scores: 3, 7, 10, 15

Subtract 3 points from the score X=3

What is referred to by the term expected frquencies?

The frequencies computed from the null hypothesis

What is referred to by the term observed frequencies

The frequencies found in the sample data

Last week Sarah had exams in math and in Spanish. On the math exam, the mean was μ = 40 with σ = 5, and Sarah has a score of X = 45. On the Spanish exam, the mean was μ = 60 and σ = 8, and Sarah had a score of X= 68. For which class should Sarah expect a better grade?

The grades should be the same because the two exam scores are in the same location.

A recent study reports that students who just finished playing a sprosocial video game were more likelu to help others than student who had played a neutral of antisocial game. For this study, what is the independent variable?

The kind of game given to the students

How does the difference between fe and fo influence the outcome of a chi-square test?

The larger the difference, the larger the value of chi-squar and the greater the likelihood o rejecting the null hypothesis

Which of the following is an accurate definition for the power of a statistical test?

The probability of rejecting a false null hypothesis

If a two-factor analysis of variance produces a statistically significant interaction, what can you conclude about the main effects?

The significance of the main ffects is not related to the significance of the interaction?

A researchers used a sample of n = 50 individuals to determine whether they are any preferences between two new deigns for a smart phone. If the data produce a chi-square statistic of X2 = 6.00 what decision should the researcher make?

There is a significant preference for alpha = .05 but not for alpha = .01

In an independent measure ANOVA, individual difference contibute to the variance in a numerator and in the denominator of the F-ration. For a repeated measures ANOVA, what happens to the individual differences in the denominator of the F-ration?

They are measured and subtracted out in the second stage of the analysis.

You complete a hypothesis test using alpha= .05, and based on the evidence from the ample, your decision is to reject the null hypothesis. If the treatment actually does have an effect which of the following is true?

Tiy gace nade rge cirrecr decusuib

Under what circumstance is the median likely to produce a better measure of central tendency than the mean?

With an extremely skewed distribution

A set of X and Y scores has Mx = 4, SSx - 10, My = 5, SSy = 40, and SP = 20. what is the regression equation for the predicting Y from X?

Y = 2X -3

A linear regression equation has b = 3 and a = -6. what is the predicted value of Y for X = 4?

Y=6 (Y hat)

You complete a hypothesis test using alpha = .05, and based on the evidence from the sample, your decisin is to fail to reject the null hypothesis. If the treatment actually does have an effect, which of the following is true?

You have made a type 2 error

the results from a research study indicate that adolescents who watch more violent content on television also tend to engage in more violent behavior than their peers. The correlation between amount of TV violent content and amount of violent behavior is an example of

a positive correlation

If a set of exam scores forms a symmetrical distribution, what can you conclude about the students scores? a. Most of the students had relatively high scores. b. Most of the students had relatively low scores. c. About 50% of the students had high scores and the rest had low scores. d. It is not possible to draw any conclusions about students' scores.

about 50% of the students had high scores and the rest had low scores

For the following distribution of quiz scores, How many individuals had a score of X = 2? X: 5,4,3,2,1. f: 6,5,5,3,2.

b

For the following frequency distribution of exam scores, what is the lowest score than an individual student achieved on the exam? X:90-94,85-89,80-84,75-79,70-74. f: 3,4,5,2,1

cannot be determined

If it is impossible to divide the existing categgories into a variable, then it is an example of a _____ variable

disctrete

Under what circumstance can a very small treatment effect be statistically significant

if a sample size big and the sample vairance is small

Under what circumstances should the chi-square statistic not be used

if fe < 5 for any cell.

Under what circumstances wil the distribution of sample means be normal?

if the popilation is normal or if the sample size is greater than 30

What is the most likely shape for a distribution with a mean of 40 and a mode of 45?

negatively skewed

Students in an introductory art class are classified as art majors and non-art majors. What scale of measurement is being used to classify the students?

nominal

Determining the class standing (1st, 2nd, and so on) for the graduating seniors at a high school would involve measurement on a(n) _____ scale of measurement.

ordinal

for a normal population with a mean if μ = 80 and a standard deviation of σ = 10, what is the probability of obtaining a sample mean greater than M = 75 for a sample of n = 25 scores?

p = 0.9938

A researcher uses an anonymous survey to investigate the television-viewing habits of American adolescents. The goal of the research is to determine the average number of hour each day that American adolescent spend watching television. The researcher is truing to determine a number that is an example of a

parameter

A researcher uses an anonymous survey to investigate the television-viewing habits of American adolescents. The entire group of american adolescents is an example of a

population

A population of scores has a mean of μ = 26, a median of 23, and a mode of 22. What is the most likely shape for the population distribution?

positively skewed

A repeated-measures analysis of variance for a study comparing three treatment condition with a sample of n = 10 participants, produces an F-ration of F = 5.40. For this result, which of the following is the correct statistical decision?

reject the null hypothesis with alpha = .05 but not with alpha = .01

What s the sample variance and the estimated standard error for a sample of n = 9 scores with SS = 72

s^2 0 9 and Sm = 1

A set of 10 scores has SS = 90. If the scores are a sample, the sample variance is ____ and if the scores are a population, the population variance is ____.

s^2 = 10; σ^2 = 9

A researcher is interested in the eating behavior of rats and selects a group of 25 rats to be tested in a research study. The group of 25 rats in an example of a ______.

sample

A researcher records the change in weight (gain or loss) during the first semester of college for each individual in a group of 25 freshmen and calculates the average change in weight. The average is an example of a _____.

statistic

With a α= .01, the two-tailed critical region for a t test using a sample of n = 16 subject would have boundaries of

t = +2.947

A sample of n = 25 individuals is selected from a population with µ = 80, and a treatment is administered to the sample. What is expected if the treatment has no effect?

the sample mean should be close to 80 and should lead you to fail to reject the null hypothesis.

what additional information is obtained by measuring two individuals on an internal scale compared to an ordinal scale?

the size of the difference.

Which of the following is a fundamental difference between the t statistic and a z-score

the t statistic uses the sample variance in place of the population variance

A researcher selects a sample and administers a treatment to the individuals in the sample. If the sample is used for a hypothesis test, what does the alternative hypothesis (H1) say about the treatment?

the treatment causes a change in the scores.

A researcher selects a sample and administers a treatment to the individuals in the sample. If the sample is used for a hypothesis test, what does the null hypothesis (Ho) say about the treatment?

the treatment has no effect on the scores

Tiy complete a hypothesis test using alpha = .05, and based on the evidence from the sample, your decision is to reject the null hypothesis. If the treatment actually has no effect, which of the following is true

you have made a Type 1 error

Which of the following z-score values represents the location farthest from the mean?

z = -2.00

For a population with a standard deviation of σ = 6, what is the z-score corresponding to a score that is 12 points above the mean?

z=2

A random sample of n = 4 scores is obtained from a population with a mean of μ = 80 and a standard deviation of σ = 10. If the sample mean is M = 90, what is the z-score for the sample mean?

z=2.00

a population of scores has μ = 50 and σ = 5. If every score in the population is multiplied by 3, then what are the new values for the mean and standard deviation?

μ = 150 and σ = 15.

a population has μ = 50 and σ = 5. If 10 points are added to every score in the population, what are the new values for the mean and standard deviation?

μ = 60 and σ = 5

On an exam with μ = 52, you have a score of X = 56. Which value for the standard deviation would give you the highest position in the class distribution?

σ = 2

a researcher administers a treatment to a sample of participant selected from a population with μ = 80. If the researcher obtain a sample mean of M = 88, which combination of factors is most likely to result in rejecting the null hypothesis

σ = 5 and n = 50