Deck 12: Understanding Research Results: Describ-Ingvariables and Relationships Among Them

Question 1

Restricting the range of a variable ___________ the effect on the correlation coefficient.

A) increases
B) decreases
C) has no effect on
D) changes the direction of

Answer 1

B

Question 2

Brewster measures the height and age of four and five year-olds.To his surprise,he finds no correlation between height and age.What is most likely responsible for his results?

A) Age and height are not related.
B) A curvilinear relationship exists between the variables.
C) He has restricted the range of the variables.
D) There is too much variability in the sample to accurately calculate a correlation coefficient.

Answer 2

C

Question 3

In a _____,a separate and distinct _____ is drawn to represent the number of people who received each possible score.

A) polygon;bar
B) bar graph;line
C) bar graph;bar
D) polygon;pie slice

Answer 3

C

Question 4

Ratio scales

A) have arbitrary zero points.
B) have an absolute zero point.
C) cannot be used in behavioural research.
D) are used to measure personality traits.

Question 5

Structural equation models

A) are developed after the data are analyzed and interpreted.
B) are expected patterns of relationships among a set of variables.
C) can only be used to explain results of laboratory experiments.
D) can only be used to explain results of field experiments.

Question 6

A teacher writes the results of a test on the board: 7 students received As,10 students received Bs,18 students received Cs,4 students received Ds,and 1 student received an F.In statistical terms,this is a

A) measure of central tendency.
B) measure of variability.
C) frequency distribution.
D) correlation table.

Question 7

Henry finds that for automobile owners,as the price of gasoline increases,the amount of miles they drive in a week decreases.This finding would suggest _____ relationship.

A) a positive
B) a negative
C) a curvilinear
D) no

Question 8

John finds the Pearson r correlation coefficient between variable A and variable B to be 0.00.Before concluding there is no relationship between the variables,John should

A) use a different set of participants.
B) restrict the range from which he samples.
C) construct a scatterplot of the data.
D) calculate the effect size for the relationship.

Question 9

In a survey examining the number of 3^rd versus 6^th grade students who buy their lunch at school,the most appropriate description of the results would be to

A) compare group percentages.
B) correlate scores.
C) compare group means.
D) compare lunches.

Question 10

Which of the following is least correct regarding the effect size? The effect size

A) refers to the strength of association between the variables.
B) provides a scale of values that is consistent across all types of studies.
C) can only range from -1.0 to + 1.0.
D) can indicate small,medium,and large effects.

Question 11

Which one of the following would be an appropriate measure of central tendency to summarize ordinal data?

A) Mean
B) Median
C) Correlation
D) Mode

Question 12

When a line graph is employed to represent the number of subjects who received each possible score on a variable,this graph is called a frequency _____.

A) model
B) polygon
C) histogram
D) bar graph

Question 13

In graphically depicting frequency distributions,_____ are used to display categorical variables while _____ are used to display quantitative variables.

A) polygons;bar graphs
B) bar graphs;histograms
C) histograms;pie charts
D) pie charts;bar graphs

Question 14

In studying the effect of temperature on ice cream cone sales,a researcher could record the number of ice cream cones sold on cold versus hot days.The researcher would be most interested in

A) comparing group performance.
B) comparing group means.
C) correlating scores.
D) comparing the type of ice cream sold.

Question 15

In a perfect positive relationship between two variables

A) knowing an individual's score on one variable will allow us to predict exactly what his or her score will be on the other variable.
B) the correlation coefficient would range between -1.0 and +1.0.
C) all of the scores on one variable will be the same as the scores on the other variable.
D) the graphic representation would be a flat line.

Question 16

An ordinal scale of measurement lacks which one of the following properties of a scale?

A) Equal orders
B) Unequal orders
C) Equal intervals
D) Unequal intervals

Question 17

The finding that "the more classes a person takes,the more money they spend on textbooks" illustrates _____ relationship.

A) a positive
B) a negative
C) a curvilinear
D) no

Question 18

Dr.Greentree finds the r² value between days of sunlight (X)and plant growth (Y)to be +.48.Dr.Greentree can conclude

A) 48% of plants will grow on sunny days.
B) plants will grow 48% taller on sunny days.
C) 48% of the variability in plant growth can be accounted for by the number of days of sunlight.
D) plants will grow 48% less on cloudy days.

Question 19

Which of the following is NOT true of the standard deviation? It

A) indicates the average deviation of scores from the mean.
B) is the square of the variance.
C) becomes larger the further the scores are from the mean.
D) is appropriate only for interval and ratio scale variables.

Question 20

Which one of the following is NOT one of the three basic ways of describing results discussed in your text?

A) Compare group percentages.
B) Compare group means.
C) Compare group assignments.
D) Correlate scores of individuals on two variables.

Question 21

An automobile repair shop reports that half of the automobiles they repair have a resale value below $8000.In this example,the $8000 represents which measure of central tendency?

A) Mean
B) Mode
C) Median
D) Standard deviation

Question 22

Why would a researcher employ structural modelling?

A) It is the only appropriate statistical techniques to use when a third variable is present.
B) It allows a researcher to test how well data fit a theoretical model that describes the relationship among variables.
C) It allows the researcher to partial out the influence of a third variable.
D) It is a more impressive statistical technique than correlation or regression.

Question 23

Researchers studying the effectiveness of a diet on heart disease separated the study's participants into two groups,those with Type A personalities and those with Type B personalities.What scale characterizes the personality variable?

A) Nominal
B) Ordinal
C) Interval
D) Ratio

Question 24

The standard deviation would be an appropriate measure of variability only if the variable is measured on a(n)_____ scale.

A) nominal
B) ordinal
C) interval
D) ratio

Question 25

After establishing that there is a reasonably high correlation between two variables,a researcher can utilize a regression equation to make predictions about the _____ variable from the _____ variable.

A) predictor;criterion
B) criterion;predictor
C) independent;dependent
D) dependent;independent

Question 26

Mean,mode,variance,and standard deviation are all examples of what type of statistics?

A) Measures of central tendency
B) Measures of dispersion
C) Inferential statistics
D) Descriptive statistics

Question 27

What is the difference between an interval and a ratio scale? A ratio scale _____ while an interval scales does not.

A) uses equal intervals
B) has an absolute zero
C) indicates order
D) gives numerical information

Question 28

A researcher finds that out of 400 pet owners surveyed,250 own only a dog,125 own only a cat,and 25 own only a bird.Which measure of central tendency is the most appropriate for this data?

A) Mean
B) Median
C) Mode
D) Standard deviation

Question 29

The measure of central tendency that reflects the most frequent score is the

A) mean.
B) median.
C) mode.
D) range.

Question 30

Any set of scores may be described by measures of ________ and ________.

A) chance variance;error variance
B) central tendency;variability
C) independent variables;dependent variables
D) probability;significance

Question 31

A teacher writes the results of a test on the board: 10 students received As,14 students received Bs,18 students received Cs,2 students received Ds,and 1 student received an F.The grade of C would represent which measure of central tendency?

A) Mean
B) Mode
C) Median
D) Standard deviation

Question 32

At the beginning of the season,a sports writer gives her prediction of teams that will finish in the top three places in the eastern,central,and western divisions.Her prediction would be an example of using which type of measurement scale?

A) Nominal
B) Ordinal
C) Interval
D) Ratio

Question 33

Which one of the following is NOT a measure of central tendency?

A) Mean
B) Median
C) Meridian
D) Mode

Question 34

The correlation coefficient

A) indicates the amount of spread in the distribution of scores.
B) is a measure of central tendency.
C) is a measure of variability.
D) is a statistic that describes how strongly variables are related to one another.

Question 35

Which one of the following scales of measurement lacks numeric properties?

A) Nominal
B) Ordinal
C) Interval
D) Ratio

Question 36

A(n)_____ allows a researcher to statistically control for the influence of a third variable.

A) criterion assessment
B) effect size
C) multiple correlation
D) partial correlation

Question 37

A common trick when bar graphs are used to mislead readers

A) is to exaggerate the distance between points on the x axis
B) is to exaggerate the distance between points on the y axis.
C) is to use bright colours for the variable they want exaggerated.
D) is to minimize the distance between points on the y axis.

Question 38

Multiple correlation is a technique for

A) increasing accuracy of prediction.
B) multiplying correlation coefficients.
C) making measures more reliable.
D) determining causal relationships between variables.

Question 39

A host of a home repair program rates the difficulty of various home improvement projects.He assigns the level of difficulty by using hammers: 3 for very difficult,2 for moderate,and 1 for easy.This measure is an example of a(n)_____ scale.

A) nominal
B) ordinal
C) interval
D) ratio

Question 40

Which one of the following would be an appropriate measure of central tendency to summarize interval data?

A) Mean
B) Median
C) Mode
D) Mean,median,or mode would be appropriate.

Question 41

After obtaining the correlation between two variables,a researcher calculates a regression equation.This equation can be used to

A) predict a person's score on one variable when only the score on a second variable is known.
B) control third variables.
C) predict scores on a third variable of interest.
D) determine effect size.

Question 42

A correlation coefficient indicates the ________ and ________ of the relationship between two variables.

A) nature;shape
B) direction;strength
C) scatter;strength
D) direction;distribution

Question 43

Which statement is least correct regarding the correlation coefficient?

A) The absolute size of r indicates the strength of the relationship.
B) The values of r can range from -1.0 to +1.0.
C) The correlation coefficient indicates whether there is a positive linear or negative linear relationship.
D) The sign of the correlation coefficient indicates the strength of the relationship.

Question 44

All correlation coefficients

A) are positive.
B) are negative.
C) range from -1.00 to +1.00.
D) use interval data.

Question 45

A professional baseball scout uses the batting average,on base percentage,throwing ability,and running speed of amateur baseball players to predict their success as professional baseball players.This strategy would be an example of using a(n)_____ as a predictor of likelihood of success.

A) effect size
B) multiple correlation
C) practicality assessment
D) criterion variable assessment.

Question 46

The _____ is a general term that refers to the strength of association between variables.

A) statistical index
B) effect size
C) standard deviation
D) linear degree

Question 47

An interval scale is preferable to an ordinal scale because

A) simpler statistics can be used.
B) it rank orders individuals on some characteristic.
C) sophisticated statistics can be used.
D) it allows the measurement of individual differences.

Question 48

Which one of the following is not a measure of variability?

A) Standard variance
B) Range
C) Variance
D) Standard deviation

Question 49

A regression equation is used to

A) determine the strength of the relationship between X and Y.
B) determine the causal relationship between X and Y.
C) predict a score on Y from a known score on X.
D) predict the difference between scores on X from the scores on Y.

Question 50

Multiple correlation utilizes many _____ variables and one _____ variable.

A) interval;ratio
B) ratio;interval
C) predictor;criterion
D) criterion;predictor

Question 51

A researcher measures the time it takes for subjects to press a button following a signal.This is a(n)________ measure.

A) nominal scale
B) ratio scale
C) ordinal scale
D) interval scale

Question 52

The Pearson product-moment correlation coefficient (r)is unable to detect

A) curvilinear relationships.
B) positive linear relationships.
C) negative linear relationships.
D) instances of no relationship.

Question 53

A negative value of r means that

A) there is no relationship between the two variables.
B) those who score high on one variable tend to score low on the other.
C) those who score high on one variable tend to score high on the other.
D) there was a mistake in calculating the value of r.

Question 54

In a perfect relationship between two variables,r²

A) would equal 0.
B) would equal +1.00.
C) would equal -1.00.
D) would be less than the value of r.

Question 55

Three celebrity judges rank order the finalists in a talent contest from the most to the least talented.This process would be an example of using which type of measurement scale?

A) Ratio
B) Interval
C) Ordinal
D) Nominal

Question 56

Measures of _____ indicate how scores are spread out in a distribution,while measures of _____ indicate how a sample scores as a whole.

A) error;true score
B) probability;significance
C) the mode;the median
D) variability;central tendency

Question 57

Jim examines the effect of type of music (jazz,rock,rap)on task performance.Type of music represents which type of measurement scale?

A) Ratio
B) Interval
C) Ordinal
D) Nominal

Question 58

A researcher obtains a -.87 correlation between job applicants' ages and their likelihood to be hired,but she thinks job skills may be an important influence.She should calculate a(n)

A) correlation coefficient between age and hiring likelihood.
B) inter-rater reliability coefficient.
C) partial correlation coefficient.
D) regression equation.

Question 59

Which one of the following statistics indicates how much scores differ from each other?

A) Mean
B) Median
C) Standard deviation
D) Central tendency

Question 60

Mel finds the relationship between alcohol consumption and reaction time is -.63.However,the relationship between coffee consumption and reaction time is +.52.Mel can conclude

A) the relationship between alcohol consumption and reaction time is weaker than the relationship between coffee consumption and reaction time.
B) the relationship between alcohol consumption and reaction time is stronger than the relationship between coffee consumption and reaction time.
C) the direction of the relationship between alcohol consumption and reaction time is approximately the same as the relationship between coffee consumption and reaction time.
D) that alcohol consumption is directly related to coffee consumption.