Psychology statistics

What is the value of Σ(X - 2)² for the scores 2, 3, 5?

10

What is the value of Σ(X - 2) for the scores 2, 3, 5?

4

A doctor is measuring children's heights to the nearest ½ inch and obtains scores such as 40.0, 40.5, 41.0, and so on. What are the real limits for a score of X = 42?

41.75 and 42.25

For the following distribution, what is the width of each class interval? X f 20-24 2 15-19 5 10-14 4 5-9 1

5

A set of scores ranges from a high of X = 34 to a low of X = 24 and has a mean of 29. Which of the following is the most likely value for the standard deviation for these scores?​

5 points

Parameter

A parameter is a value—usually a numerical value—that describes a population. A parameter is usually derived from measurements of the individuals in the population.

What is the value of Σ(X - 2 )2 for the scores 2, 3, 5? a. 8 b. 10 C. 16 D. 36

B. 10

For the data in the following table, what is the value of ΣX? X: 4, 3, 2, 1 F: 1, 2, 4, 2 a. 10 b. 15 c. 20 d. Cannot be determined from the table

C. 20

In a grouped frequency distribution, one interval is listed as50-59. Assuming that the scores are measuring a continuous variable, what are the real limits for this interval? A. 50 and 59 B. 50.5 and 59.5 C. 45.9 and 59.5 D. 45.9 and 60.5

C. 45.9 and 59.5

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.

C. About 50% of the students had high scores and rest had low scores

Which of the following is done last in the order of operations? a. Squaring b. Multiplication C. Addition d. Summation (Σ)

C. Addition

What kind of measurement scale is necessary to conclude that one score is twice a big as another? a. Ordinal b. Interval C. Ratio D. Interval or ratio

C. Ratio

What is the value of Σ(X + 1) for the scores 1, 0, 1, 4? a. 4 b. 6 C. 7 D. 10

D. 10

The normal distribution is an example of a. a histogram showing data from a sample. b. a polygon showing data from a sample. c. a bar graph showing data from a population. d. a smooth curve showing data from a population.

D. A smooth curve showing data from a population

For the following distribution, how many people had scores less than X = 19? X: 20-24, 15-19,10-14, 5-9 F: 2, 5, 4, 1 a. 5 b. 10 c. 11 d. Cannot be determined

D. Cannot be determined

For the following frequency distribution of exam scores, what is the lowest score on the exam? X: 90-94, 85-89, 80-84, 75-79, 70-74 F: 3, 4, 5, 2, 1 a. X = 70 b. X = 74 c. X = 90 d. Cannot be determined

D. Cannot be determined

A researcher is curious about the average monthly cell phone bill for high school students in the state of Florida. If this average could be obtained, it would be an example of a ______. a. sample b. statistic C. Population D. Parameter

D. Parameter

In a distribution with positive skew, where are the scores with the highest frequencies located?

On the left side of the distribution

Which of the following is an example of a discrete variable? The amount of weight gained for each freshman at a local college The gender of each student in a psychology class The age of each student in a psychology class The amount of time to solve a problem

The gender of each student in a psychology class

The relationship between a statistic and a parameter is the same as the relationship between ______.

a sample and a population

ΣX² means to ____

find the sum of squared x values. Square each data entry, multiply by the frequency, then find the sum.

ΣX means to___

find the total number of data entries. Multiply data scores by frequency to find the sum.

After measuring two individuals, a researcher can say that Tom's score is 4 points higher than Bill's. The measurements must come from a(n) _______ scale.

interval or ratio

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

Using letter grades (A, B, C, D, and F) to classify student performance on an exam is an example of measurement on a(n) _______ scale of measurement.

ordinal

Instead of showing the actual number of individuals in each category, a population frequency distribution graph usually shows a(n)___.

relative frequency

Although a research study is typically conducted with a relatively small group of participants known as a _________, most researchers hope to generalize their results to a much larger group known as a _________.

sample; population

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 verbal 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 an experiment comparing two methods of teaching social skills training to autistic children, the independent variable is _______ and the dependent variable is _______.

teaching methods; the social skills that are learned

A researcher is measuring the amount of time needed to solve a set of anagrams for a sample of n = 15 students. However, one of the participants fails to solve the problems so the researcher has an undetermined score. What is the best measure of central tendency for these data?​

the mean

In a grouped frequency distribution, one interval is listed as 50-59. Assuming that the scores are measuring a continuous variable, what are the real limits for this interval?

​49.5 and 59.5

​A set of scores ranges from a high of X = 72 to a low of X = 28. If these scores were put in a grouped frequency distribution table, what would be the best choice for the interval width? ​2 points ​7 points ​10 points 5 points

5 points

What is the value of (ΣX)² for the scores 1, 5, 2?

64

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 a. Symmetrical b. Positively skewed c. Negatively skewed d. Normal

B. Positively skewed

To find the total number of scores in a distribution find the sum for____

the frequency.

​What is the total number of scores for the distribution shown in the following table?​ X f 4 3 3 5 2 4 1 2

14

For the data in the following table, what is the value of ΣX?​ X f 4 1 3 2 2 4 1 2

20

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

10%

Population

A population is the set of all the individuals of interest in a particular study.

sample

A sample is a set of individuals selected from a population, usually intended to represent the population in a research study.

statistic

A statistic is a value—usually a numerical value—that describes a sample. A statistic is usually derived from measurements of the individuals in the sample.

A biologist records the number of trout, bass, perch, and other types of fish caught in a local lake during a 2week period.If the results are organized in a frequency distribution graph, what kind of graph should be used? a. A bar graph b. A histogram C. A polygon D. Either a histogram or polygon

A. a bar graph

What is the value of Σ(X - 1)2 for the scores 1, 2, 1, 4? a. 10 b. 16 C. 36 D. 49

A. 10

What is the value of Σ(X - 2) for the scores 2, 3, 5? a. 4 b. 6 C. 8 D. 10

A. 4

What is the value of ΣX + 1 for the scores 1, 0, 2, 4? a. 8 b. 10 C. 11 D. 14

A. 8

After recording the final grade (A, B, C, D, E) for each individual in a class of n = 26 students, the professor would like to display the grade distribution in a frequency distribution graph. What kind of graph should be used? a. A bar graph b. A histogram C. A polygon D. Either a histogram or polygon

A. A bar graph

What kind of frequency distribution graph shows the frequencies as bars that are separated by spaces? a. A bar graph b. A histogram C. A polygon D. All of these

A. A bar graph

If a set of exam scores forms a negatively skewed 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.

A. Most of the students had relatively high scores

Students in an introductory art class are classified as art majors and nonart majors. What scale of measurement is being used to classify the students? a. Nominal b. Ordinal C. Interval D. Ratio

A. Nominal

If a distribution of scores is shown in a bar graph, you know that the scores were measured on a(n) _________ scale of measurement. a. nominal or ordinal b. ordinal or interval C. Interval or ratio D. Discrete or continuous

A. Nominal or ordinal

A researcher uses an anonymous survey to investigate the televisionviewing habits of American adolescents. The goal of the research is to determine the average number of hours each day that American adolescents spend watching television. The researcher is trying to determine a number that is an example of a _____. a. parameter b. statistic C. population D. sample

A. Parameter

American adolescents spends watching television. The researcher is trying to determine a number that is an example of a_________?

A. Parameter

Although a research study is typically conducted with a relatively small group of participants known as a _________ most researchers hope to generalize their results to a much larger group known as a __________. A. Sample, population B. Statistic, sample C. Population, sample D. Parameter, population

A. Sample, population

What is the first step to be performed in the following mathematical expression, ΣX? a. Square each score b. Add the scores C. Add the squared scores D. Square the sum of the scores

A. Square each score

What is the shape of the distribution for the following set of data? X: 5, 4, 3, 2, 1 F: 5,3, 1, 3, 5 A. Symmetrical B. Positively skewed C. Negatively skewed D. Normal

A. Symmetrical

If the following distribution were shown in a histogram, the width of the bar above the 15-19 interval would reach from _____ to _____. X: 20-24, 15-19, 10-14, 5-9 F: 2, 5, 4, 1 a. X = 14.5 to X = 19.5 b. X = 15.5 to X = 18.5 c. X = 15.5 to X = 19.5 d. X = 15.0 to X = 19.0

A. X= 14.5 to x= 19.5

What is the shape of the distribution for the following set of data? X: 5,4,3,2,1 F: 5,3,1,3,5 a. Symmetrical b. Positively skewed c. Negatively skewed d. Normal

A.symmetrical

What is the value of ΣX + 1 for the scores 1, 6, 3? a. 10 b. 11 C. 13 D. 16

B. 11

A skewed distribution typically has _____ tail(s) and a normal distribution has ____ tail(s). a. 1; 1 b. 1; 2 C. 2; 1 D. 2; 2

B. 1; 2

What is the value of ΣX2 for the scores 1, 0, 2, 4? a. 14 b. 21 C. 28 D. 49

B. 21

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 a. 1 b. 3 c. 5 d. Cannot be determined

B. 3

For the following frequency distribution of exam scores, how many students had scores lower than X = 80? X: 90-94, 85-89, 80-84, 75-79, 70-74 F: 3, 4, 5, 2, 1 a. 2 b. 3 c. 7 d. Cannot be determined

B. 3

What kind of frequency distribution graph shows the frequencies as bars, with no space between adjacent bars? a. A bar graph b. A histogram C. A polygon D. All of these

B. A Histogram

In a distribution with positive skew, scores with the highest frequencies are _____. a. on the right side of the distribution b. on the left side of the distribution C. In the middle of the distribution D. Represents at two distinct peaks

B. On the left side of the distribution

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. a. nominal b. ordinal C. Interval D. Ratio

B. Ordinal

The participants in a research study are classified as high, medium, or low in selfesteem. What measurement scale is being used to classify selfesteem? a. Nominal b. Ordinal C. Interval D. Ratio

B. Ordinal

Using letter grades (A, B, C, D, and E) to classify student performance on an exam is an example of measurement on a(n) _______ scale of measurement. a. nominal b. ordinal C. Interval D. Ratio

B. Ordinal

What term is used to describe the shape of a distribution in which the scores pile up on the lefthand side of the graph and taper off to the right? a. Symmetrical b. Positively skewed C. Negatively skewed D. Normal

B. Positively skewed

A characteristic, usually a numerical value, which describes a sample is called a _________ A. Parameter B. Statistics C. Variable D. Constant

B. Statistic

What additional information is obtained by measuring two individuals on an ordinal scale compared to a nominal scale? a. Whether the measurements are the same or different b. The direction of the difference c. The size of the difference d. None of the other options is correct

B. The direction of the difference

You are instructed to subtract 4 points from each score and find the sum of the resulting values. How would this set of instructions be expressed in summation notation? a. ΣX - 4 b. Σ (X - 4) C. 4 - ΣX D. Σ(4 - X)

B. Σ (X - 4)

For the following frequency distribution of exam scores, how many students had scores higher than X = 79? X: 90-94, 85-89, 80-84,75-79,70-74 F: 3, 4, 5, 2,1 a. 7 b. 12 c. 19 d. Cannot be determine

B.12

Organizing a set of scores in a table is a table is an example of using A. Parameter B. Statistics C. Descriptive statistics D. Inferential statistics

C. Descriptive statistics

If it is impossible to divide the existing categories of a variable, then it is an example of a _____ variable. a. independent b. dependent C. Discrete D. Continuous

C. Discrete

Which types of graphs are used for data from an interval scale? a. Histograms and bar graphs b. Polygons and bar graphs C. Histograms And polygons D. Histograms, bar graphs, polygons

C. Histograms and polygons

For statistical purposes, it usually is not important to differentiate between which two scales of measurement? a. Nominal and ordinal b. Ordinal and interval C. Interval and ratio D. Nominal and interval

C. Interval and ratio

The students in a psychology class seemed to think that the midterm exam was very easy. If they are correct, what is the most likely shape for the distribution of exam scores? a. Symmetrical b. Positively skewed C. Negatively skewed D. Normal

C. Negatively skewed

What is the shape of the distribution for the following set of data? Scores: 1, 2, 3, 3, 4, 4, 4 5, 5, 5, 5, 6 a. Symmetrical b. Positively skewed c. Negatively skewed d. Normal

C. Negatively skewed

If a set of scores is displayed in a frequency distribution bar graph, what scale of measurement was used to measure the scores? a. Nominal b. Ordinal C. Nominal or ordinal D. Interval or ratio

C. Nominal or ordinal

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 _________. a. sample b. statistic c. Population d. Parameter

C. Population

What is the final step to be performed when computing Σ(X - 2)2? a. Square each value b. Subtract 2 points from each score C. Sum the squared values d. Subtract 22 from each X2 value

C. Sum the squared values

A recent study reports that students who just finished playing a prosocial video game were more likely to help others than students who had played a neutral or antisocial game. For this study, what is the independent variable? a. The students who were given the prosocial game b. The students who were given the neutral or antisocial game c. The kind of game given to the students d. The helping behavior of the students

C. The kind of game given to the students

What additional information is obtained by measuring two individuals on an interval scale compared to a ordinal scale? A. Whether the measurements are the same or different B. The direction of the difference C. The size of the difference D. None of the other options is correct

C. The size of the difference

In a frequency distribution graph, frequencies are presented on the _________, and the scores (categories) are listed on the ________. a. X axis; Y axis b. horizontal line; vertical line C. Y axis; X axis D. Class interval ; horizontal line

C. Y axis; X axis

You are instructed to subtract 4 points from each score, square the resulting value, and find the sum of the squared numbers.How would this set of instructions be expressed in summation notation? a. ΣX - 42 b. (ΣX - 4)2 c. Σ(X - 4)2 d. ΣX2 - 4

C. Σ(X - 4)2

What is the value of Σ(X + 1) for the scores 2, 4, 7? a. 10 b. 11 c. 13 d. 16

D. 16

What is the value of (ΣX)2 for the scores 1, 0, 2, 4? a. 14 B. 21 c. 28 D. 49

D. 49

What is the value of (ΣX)2 for the scores 1, 5, 2? A. 10 B. 16 C. 30 D. 64

D. 64

A researcher surveys a sample of n = 200 college students and asks each person to identify his or her favorite movie from the past year. If the results were presented in a frequency distribution graph, what kind of graph would be appropriate? a. A histogram b. A polygon C. Histogram or a polygon D. A bar graph

D. A bar graph

For the following frequency distribution, what is ΣX? X: 30-34, 25-29, 20-24, 15-19, 10-14 F: 1, 1, 3, 3, 2 a. 8 b. 90 c. 110 d. Cannot be determined

D. Cannot be determined

A researcher collects a sample of n = 20 Introductory Psychology textbooks and records the number of pages in each book. The results are then placed in a grouped frequency distribution table using intervals of 099 pages, 100-199 pages, 200, 299 pages, and so on. If the results were converted into a frequency distribution graph, what kind of graph should be used? a. A bar graph b. A histogram C. A polygon D. Either a histogram or a polygon

D. Either a histogram or a polygon

A frequency distribution graph represents frequencies with vertical bars without space between them. What scale of measurement was used to measure the scores? a. Nominal b. Ordinal C. Nominal or ordinal D. Interval or ratio

D. Interval or ratio

After measuring two individuals, a researcher can say that Tom's score is 4 points higher than Bill's. The measurements must come from a(n) _______ scale. a. nominal b. ordinal C. Interval D. Interval or ratio

D. Interval or ratio

If a set of scores is displayed in a frequency distribution polygon, what scale of measurement was used to measure the scores? a. Nominal or ordinal b. Interval C. Ratio D. Interval or ratio

D. Interval or ratio

What frequency distribution graph is appropriate for scores measured on a nominal scale? a. Only a histogram b. Only a polygon C. Either a histogram or polygon D. Only a bar graph

D. Only a bar graph

What scale of measurement is being used when a teacher measures the number of correct answers on a quiz for each student? a. Nominal b. Ordinal C. Interval D. Ratio

D. Ratio

A researcher uses an anonymous survey to investigate the television viewing habits of American adolescents. Based on the set of 356 surveys that were completed and returned, the researcher finds that these students spend an average of 3.1 hours each day watching television. For this study, the set of 356 students who returned surveys is an example of a _______. A. Parameter B. Statistics C. Population D. Sample

D. Sample

What is the final step to be performed in the mathematical expression, (ΣX)2? a. Square each score b. Add the scores C. Add the squared scores D. Square the sum of the scores

D. Square the sum of the scores

Which of the following measuring scales are displayed by frequency distribution polygons? Either interval or ratio scales Only ratio scales Either nominal or ordinal scales Only nominal scales

Either interval or ratio scales

sampling error

Sampling error is the naturally occurring discrepancy, or error, that exists between a sample statistic and the corresponding population parameter.

Which of the following is an example of a continuous variable? The gender of each student in a psychology class The amount of time to solve a problem The number of males in each class offered by the college The number of children in a family

The amount of time to solve a problem

A group of quiz scores is shown in a histogram. If the bars in the histogram gradually decrease in height from left to right, what can you conclude about the set of quiz scores?

There are more low scores than there are high scores.

What is the first step to be performed when computing Σ(X + 2)2? a. Square each value b. Add 2 points to each score C. Sum the squared values D. Sum the (X +2) values

b. Add 2 points to each score

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 hours each day that American adolescents spend watching television. The researcher is trying 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. Based on the set of 356 surveys that were completed and returned, the researcher finds that these students spend an average of 3.1 hours each day watching television. For this study, the set of 356 students who returned surveys is an example of a _______.

sample