Research Methods Final Review

nonequivalent groups

-groups compared in a study where participants are not randomly assigned

latin square

-partial counterbalancing technique where the number of orders of conditions used is equal to the number of conditions in the study

random assignment

-participants are randomly assigned to levels of the independent variable in an experiment to control for individual differences as an extraneous variable

solomon four-group design

-pretest/posttest design with two sets of nonequivalent groups, one set that takes the pretest and posttest and one set that takes only the posttest

t-test

-significance test used to compare means

main effect

-test of the differences between all means for each level of an independent variable in an ANOVA

interaction effect

-tests the effect of one independent variable at each level of another independent variable in an ANOVA

null hypothesis

-the hypothesis that an effect or relationship does not exist (or exists in the opposite direction of the alternative hypothesis) in the population

scientific/alternative hypothesis

-the hypothesis that an effect or relationship exists (or exists in a specific direction) in the population

analysis of variance (ANOVA)

-used for designs with three or more samples means

a

the best way to avoid the effects of maturation is to include a _________ group that does receive the treatment to allow a comparison of groups that have similar experiences except for the treatment: a) control b) placebo c) experimental d) investigational

a

these are events that occur during the course of a study to all or individual participants that can result in bias: a) history effects b) testing effects c) group differences d) maturation

discrete trials design

-a small n design that involves a large number of trials completed by one or a few individuals and conducted to describe basic behaviors

baseline design

-a small n design that involves baseline measurement of behavior as compared with measures of behavior during the implementation of a treatment

ABA/reversal design

-a small n, baseline design where the baseline behavior is measured, followed by implementation of a treatment, followed by another baseline measure after the treatment has ended

linear regression

-a statistical technique that determines the best fit line to a set of data to allow prediction of the score on one variable from the score on another variable

interrupted time series design

-a time series design where the "treatment" is an independent event, such as a historical event

non interrupted time series design

-a time series design where the "treatment" is implemented by the researcher

pretest-posttest design

-a type of research design (often a quasi-experiment) where behavior is measured both before and after a treatment or condition is implemented

experiment

-a type of research design that involves manipulation of an independent variable, allowing control of extraneous variables that could affect the results

quasi-experiment

-a type of research design where a comparison is made, as in an experiment, but no random assignment of participants to groups occurs

independent variable

-a variable in an experiment that is manipulated by the researcher such that the levels of the variable change across or within subjects in the experiment

multivalent variable

-a variable that includes three or more levels -a design is considered this if there is only one independent variable that contains three or more levels

power

-ability of a significance test to detect an effect or relationship when one exists (equal to 1 - the probability of a type II error)

post hoc tests

-additional significance tests conducted to determine which means are significantly different for a main effect

small-n design

-an experiment conducted with one or a few participants to better understand the behavior of those individuals

factorial design

-an experiment or quasi that includes more than one independent variable

confounding variable

-an extraneous factor present in a study that may affect the results

homogeneity of variances

-assumption of between subjects t-tests and ANOVAs that the variance in the scores in the population is equal across groups

sphericity assumption

-assumption of the repeated measures (within subjects) ANOVA that pairs of scores in the population have equal variances

regression towards the mean

-can occur when participants score higher or lower than their personal average; the next time they are tested, they are more likely to score near their personal average, making scores unreliable

within-subjects variable

-each participant experiences all levels of the variable

between-subjects variable

-each participant experiences only one level of the independent variable

type I error

-error made in significance test when the researcher rejects the null hypothesis when it is actually true

history effects

-events that occur during the course of a study to all or individual participants that can result in bias

baseline measurement

-measurement of behavior without a treatment used as a comparison

maturation

-natural changes that occur to the participants during the course of a study that can result in bias

degrees of freedom

-number of score that can vary in the calculation of the statistic

testing effects

-occur when participants are tested more than once in a study with early testing affecting later testing

carryover effects

-occur when participants' experience in one condition affects their behavior in another condition of the study

attrition/mortality

-occurs when participants choose not to complete a study

d

if a researcher wishes to predict the scores on one measured variable from the scores on another measured variable, the appropriate statistical test is: a) Pearson t-test b) an independent samples t-test c) a paired/related samples t-test d) a linear regression

a

in a longitudinal design age is treated as a ___________ variable but age is treated as a ____________ variable in a cohort-sectional design: a) within-subjects/ within and between subjects b) within and between subjects/ between subjects c) between-subjects/ within-subjects d) within-subjects/ between-subjects e) between-subjects/ between-subjects

b

in the video we watched in class about the drinking age, the natural experiment the researchers conducted was: a) a cohort-sequential design b) an ABA design c) a baseline design d) a discrete trials design

chi-square test

-a significance test used to determine if a linear relationship exists between two variables measured on interval or ratio scales

matched design

-a between subjects experiment that involves sets of participants matched on specific characteristic with each member of the set randomly assigned to a different level of the independent variable

generation/cohort effects

-a confound that can occur in cross-sectional designs due to different experiences that different generations have

counterbalance

-a control used in within-subjects experiments where equal numbers of participants are randomly assigned to different orders of the conditions

cross-sectional design

-a developmental between subjects design where multiple samples of participants of different ages are tested once

cohort-sequential design

-a developmental within and between subjects design where multiple ages are followed over time and tested at different ages

longitudinal design

-a developmental within subjects design where a single sample of participants is followed over time and tested at different ages

time series design

-a research design where patterns of scores over time are compared from before a treatment is implemented and after a treatment is implemented

critical region

-the most extreme portion of a distribution of statistical values for the null hypothesis, determined by the alpha level (typically 5%)

significant test

-the p-value is less than or equal to alpha in an inferential test, and the null hypothesis can be rejected

alpha level

-the probability level used to researchers to indicate the cutoff probability level (highest value) that allows them to reject the null hypothesis

quasi-independent/subject variable

-variable that allows comparison of participants without manipulation (i.e. no random assignment)

b

a cohort-sequential design handles some of the sources of bias present in other developmental designs by: a) manipulating age as an independent variable b) examining age effects both longitudinally and cross-sectionally c) removing all possible cohort/generation effects d) all of the above

b

a developmental psychologist compares standardized math test scores for 2nd, 5th, and 10th graders. The subjects are all tested at the same time, thus, different groups of subjects are tested, each group at a different age. This study utilizes a(n) ___________ design: a) longitudinal b) cross-sectional c) cohort-sequential d) experimental

d

a developmental psychologist conducted an experiment to examine the effect of type of text used on math performance across age groups. Fifth grade and college students studied age-appropriate math concepts using either a traditional hard copy text or an e-text available on the web. Performances on a math test of the concepts studied was then measured for students. The appropriate statistical test to analyze the data in this study is: a) a one-sample t-test b) an independent samples t-test c) a paired/related samples t-test d) an ANOVA

b

a quasi-experiment was conducted to compare men's and women's attitude about extramarital affairs. Men and women who are married were recruited to complete a survey about their attitudes. The researchers then compared scores on the survey for men and women. The appropriate statistical test to analyze the data in this study is: a) a one-sample t-test b) an independent samples t-test c) a paired/related samples t-test d) an ANOVA

a

a researcher conducted a correlational study to examine the relationship between high school GPA and extroversion. A group of high school students completed a measure of extroversion. The GPAs for these students was then obtained from their records. The appropriate statistical test to analyze the data in this study is: a) Pearson t-test b) an independent samples t-test c) a paired/related samples t-test d) an ANOVA

a

a researcher was interested in the effect of anxiety on intelligence measurement. A group of 100 individuals were placed in an anxiety-provoking situation before being given an IQ test. The scores for this group were then compared to the IQ population mean of 100. The appropriate statistical test to analyze the data in this study is: a) a one-sample t-test b) an independent samples t-test c) a paired/related samples t-test d) an ANOVA

d

a researcher who wants to test the relationship between nominal or ordinal variables should use a(n) _________ test: a) Pearson t-test b) an independent samples t-test c) a paired/related samples t-test d) chi-square

c

according to the video in class, the best explanation for the cohort effect in the increased numbers of children with autism is: a) increased vaccinations b) increased levels of mercury in the water supply c) increased awareness d) increased video games and television