Question 1

A common way to handle missing data when there are only a few missing values and the pattern seems more or less random is to:
A)substitute the mode of everyone else's score on that variable for each missing value
B)substitute the mean of everyone else's score on that variable for each missing value
C)delete the individual from the database
D)delete that particular variable from the database

Accepted Answer

Substituting the mean of everyone else's score on that variable for each missing value is the most common and simple method for handling missing data when there are only a few missing values and the pattern seems more or less random. This method helps to preserve the distributional properties of the variable and retains the maximum amount of information.

Question 2

If a participant has a missing value on an item that is part of a multi-item measure (such as 1 item not answered on a 20-item depression questionnaire), the researcher might handle this by:
A)substituting that person's average on the items that were completed
B)substituting a similar person's score on that item
C)substituting the total score on the questionnaire for that item
D)all of the above are viable options

Accepted Answer

Substituting the person's average on the completed items is the most common and recommended method for handling missing values in multi-item measures. This method preserves the individual's overall score on the measure and minimizes the impact of missing data on the results. Substituting a similar person's score on that item or the total score on the questionnaire for that item can introduce bias and distort the results.

Question 3

Consider a study looking at the relation of gender and performance on a statistics examination. This study is about __________.
A)variance variables
B)associations among variables
C)pre-and post-testing of variables
D)dependent variables

Accepted Answer

The study is investigating the relationship or association between two variables - gender and performance on a statistics examination. Therefore, it is about associations among variables. Option A (variance variables) is not applicable as the study is not specifically looking at the variance of any particular variable. Option C (pre-and post-testing of variables) is not applicable as there is no mention of pre-testing or post-testing in the question. Option D (dependent variables) is not applicable as the question does not specify which variable is dependent and which variable is independent.

Question 4

Before running statistical analyses, researchers should check their data for:
A)skewness
B)missing data
C)outliers
D)all of the above

Accepted Answer

Researchers should check their data for skewness, as it can affect the interpretation of statistics. Missing data can also impact the validity of statistical analyses, so it is important to identify and address any missing data prior to conducting analyses. Outliers are data points that are significantly different from other data points in the dataset, and they can have a large influence on the results of statistical analyses. Therefore, it is important to check for and potentially address outliers before conducting statistical analyses. Overall, it is important to check for all of these factors in order to ensure the accuracy and validity of statistical analyses.

Question 5

A researcher should use __________ or __________ when there is one predictor variable.
A)multiple regression; correlation
B)correlation; bivariate prediction
C)Z scores; multiple regression
D)criterion variables; Z scores

Accepted Answer

When there is only one predictor variable, a researcher can use either correlation or bivariate prediction. Correlation shows the strength and direction of the relationship between two variables, and bivariate prediction allows the researcher to make predictions about one variable based on the value of another variable (in this case, the predictor variable). Multiple regression and Z scores are not necessary when there is only one predictor variable. Criterion variables are the outcome variables being predicted, but do not inform the choice of statistical method in this case.

Question 6

Consider a study comparing the effects of different paints colors (pale blue, bright red, pale yellow)in a child's play room on children's mood (rated on a 50-points scale). This study is comparing:
A)means of variables
B)modes of variables
C)nominal of association
D)levels of association

Accepted Answer

The study is comparing the mean mood score of children exposed to different paint colors. Therefore, it involves comparing means of variables.

Question 7

If a researcher decides to handle missing data on a particular item by only including those participants who answered that item, he or she must keep in mind that results will:
A)be completely valid and applicable
B)apply to all members of the population
C)only apply to the kinds of people who are likely to answer such questions
D)not be publishable

Accepted Answer

By only including participants who answered a particular item, the sample becomes non-random and therefore may not be representative of the population as a whole. The results can only be applied to the subset of individuals who answered the item, and not necessarily to all members of the population.

Question 8

Once a researcher has decided whether to utilize a t test or ANOVA (based on the number of means being compared), the next decision relates to:
A)whether to determine the mean or median of the samples
B)whether to determine the variance or standard deviation of the samples
C)whether to refer to the Z table or t table
D)whether to use a between-subjects or within-subjects design

Accepted Answer

Once a researcher has decided whether to utilize a t test or ANOVA, the next decision should be whether to use a between-subjects or within-subjects design. This decision depends on the research question and the study design. A between-subjects design compares different groups of participants, while a within-subjects design compares the same participants in different conditions. This decision will affect the interpretation of the results and the statistical power of the study, so it should be carefully considered.

Question 9

If you wish to predict the likelihood of developing breast cancer from a combination of information about genes, environment, and lifestyle the appropriate analysis would be a:
A)t test
B)chi square
C)ANOVA
D)multiple regression

Accepted Answer

Multiple regression analysis allows for the examination of the relationship between multiple predictor variables (genes, environment, lifestyle) and a single outcome variable (likelihood of developing breast cancer). This type of analysis is best suited for examining the complex relationships between multiple predictors and an outcome variable, making it the most appropriate choice for this scenario.

Question 10

The following situation(s)could result in missing data:
A)a participant accidentally skips three questions
B)an observer misses a particular behavior
C)recording devices fail during an experiment
D)all of the above

Accepted Answer

All of the above situations could result in missing data. Participants may accidentally skip questions or observers may miss behaviors, while recording devices could fail during an experiment. All of these situations would result in missing or incomplete data.

Question 11

Suppose you are testing a hypothesis about which of various professors are most favored by psychology students at a particular university. The appropriate analysis would be:
A)ANOVA
B)t test for independence
C)chi-square test
D)correlation

Accepted Answer

The answer of Suppose you are testing a hypothesis about...

Question 12

In a between-subjects design __________ people are in each group.
A)different
B)the same
C)more than 30
D)equal numbers of

Accepted Answer

In a between-subjects design, different people are assigned to each group to compare the effects of different conditions or treatments.

Question 13

Once a researcher has an idea for a research question, the next step is to:
A)run a statistical analysis
B)enter data into SPSS
C)develop a specific research plan to address the question
D)prepare a manuscript for publication

Accepted Answer

Developing a specific research plan is the next step after formulating a research question. This plan includes identifying a sample, selecting research methods, determining data collection procedures, and outlining statistical analyses. Running statistical analyses and entering data into SPSS come later in the research process once data has been collected. Preparing a manuscript for publication comes after the research has been conducted, analyzed, and interpreted.

Question 14

The appropriate type of analysis to use with rank-order scores is:
A)parametric
B)nonparametric
C)linear
D)log linear

Accepted Answer

Rank-order scores are ordinal data which do not follow a normal distribution, making nonparametric analysis the most appropriate choice. Nonparametric tests do not rely on assumptions of normality or equal variances and are based on the rankings or order of the data instead of actual values. Some examples of nonparametric tests for ranking data include the Wilcoxon Signed-Rank Test and the Kruskal-Wallis Test.

Question 15

What is meant by the phrase "data screening"?
A)typing all scores into the database
B)setting up the SPSS spreadsheet
C)labeling one's variables
D)checking data for accuracy and missing values

Accepted Answer

Data screening refers to the process of checking the data for accuracy, completeness, and missing values before analyzing it. This can involve removing outliers, identifying anomalies and errors, and ensuring that the data is formatted correctly. Therefore, choice D, checking data for accuracy and missing values, is the correct answer. Choices A, B, and C are not comprehensive enough to fully capture the essence of data screening.

Question 16

A statistical procedure involving more than one criterion or outcome variable is called a:
A)univariate test
B)multivariate test
C)rank-order test
D)chi-square test

Accepted Answer

A multivariate test is a statistical procedure involving more than one criterion or outcome variable. The other options are not correct as univariate tests involve only one variable, rank-order tests involve ordinal data, and chi-square tests are typically used for categorical data.

Question 17

Consider a study comparing the effects of different encoding methods (i.e., visual and auditory)on later retention of information. This study focuses on the arrange memory performance for each encoding modality; thus, this is a study comparing __________.
A)variance variables
B)the relationship between variables
C)the distribution of difference scores
D)the standard deviation of variables

Accepted Answer

The answer of Consider a study comparing the effects of...

Question 18

Before embarking on a new study, experienced researchers carefully plan the statistical method(s)they will use when the study is complete. Why is it important to carry out this step?
A)To ensure that there are available and appropriate methods to use when the study is done
B)To determine how many participants you will need
C)To determine the power of your planned study
D)All of the above

Accepted Answer

It is important to plan the statistical methods before starting a study to ensure that there are suitable methods available at the end, to determine the sample size required for the study, and to calculate the statistical power of the study. Therefore, all options (A, B, and C) are correct.

Question 19

If your planned study has power below 80%, you should first consider:
A)increasing the size of the samples
B)raising the study's level of significance
C)using the true population variance
D)treating the two samples as one sample

Accepted Answer

Increasing the size of the samples is the best option for increasing power. A larger sample size will decrease the standard error and increase the ability to detect a significant difference between the groups. Raising the study's level of significance is not recommended as it increases the chances of a type I error. Using the true population variance is not practical as it is rarely known in advance. Treating the two samples as one sample would not increase the power but would decrease the degrees of freedom and potentially increase the standard error.

Question 20

To figure statistical power of a planned study, one needs to:
A)decide what statistical test to use
B)make some estimate of effect size
C)carefully collect the data and analyze results
D)both A and B

Accepted Answer

To figure out statistical power, one needs to decide what statistical test to use and make some estimate of effect size. Therefore, both choices A and B are necessary to correctly calculate statistical power. Choice C is not relevant to figuring out statistical power, as it refers to the data collection and analysis after the study has been conducted.

Quiz 12: Applying Statistical Methods in Your Own Research Project

A common way to handle missing data when there are only a few missing values and the pattern seems more or less random is to:

If a participant has a missing value on an item that is part of a multi-item measure (such as 1 item not answered on a 20-item depression questionnaire) , the researcher might handle this by:

Consider a study looking at the relation of gender and performance on a statistics examination. This study is about __________.

Before running statistical analyses, researchers should check their data for:

A researcher should use or when there is one predictor variable.

Consider a study comparing the effects of different paints colors (pale blue, bright red, pale yellow) in a child's play room on children's mood (rated on a 50-points scale) . This study is comparing:

If a researcher decides to handle missing data on a particular item by only including those participants who answered that item, he or she must keep in mind that results will:

Once a researcher has decided whether to utilize a t test or ANOVA (based on the number of means being compared) , the next decision relates to:

If you wish to predict the likelihood of developing breast cancer from a combination of information about genes, environment, and lifestyle the appropriate analysis would be a:

The following situation(s) could result in missing data:

Suppose you are testing a hypothesis about which of various professors are most favored by psychology students at a particular university. The appropriate analysis would be:

In a between-subjects design __________ people are in each group.

Once a researcher has an idea for a research question, the next step is to:

The appropriate type of analysis to use with rank-order scores is:

What is meant by the phrase "data screening"?

A statistical procedure involving more than one criterion or outcome variable is called a:

Consider a study comparing the effects of different encoding methods (i.e., visual and auditory) on later retention of information. This study focuses on the arrange memory performance for each encoding modality; thus, this is a study comparing __________.

Before embarking on a new study, experienced researchers carefully plan the statistical method(s) they will use when the study is complete. Why is it important to carry out this step?

If your planned study has power below 80%, you should first consider:

To figure statistical power of a planned study, one needs to: