Multigroup Design

Demand characteristics

cues that potentially make participants aware of what the experimenter expects

social desirability

desire to give answers that make participant look good to others

what does statistically significant mean?

it is the likelihood that a relationship between two or more variables is caused by something other than chance

what is a study's "power"?

the study's ability to find real differences between our groups (i.e., when the null hypothesis is false); the probability that a study will yield significant results

how can we maximize our study's power?

increase the strength of the manipulation -- the larger the differences between our groups, the easier it will be to detect whether or not our IV influenced the DV

evaluation apprehension

anxiety or concern that participants may experience about how their answers or behaviors appear to the researcher

what type of scale items can minimize the problems associated with evaluation apprehension?

distractor items

confound

a variable that the researcher unintentionally varies along with the manipulation

nonlinear relationships

any association between variables that the use of just two comparison groups cannot uncover. these relationships, often identified on a graph as a curved or curvilinear line, help provide us with a clearer picture of how variables relate to one another.

methodological pluralism

the use of multiple methods or strategies to answer a research question

hypothesis guessing

when a participant in a study actively attempts to identify the purpose of the research

empty control group

a group that does not receive any treatment and just completes the dependent variable

multigroup design

an experimental design with three or more groups

chi-square test of independence

a statistical test in which both variables are categorical. This test generally examines if the distribution of participants across categories is different from what would happen if there were no difference between the groups.

exploratory analyses

statistical tests that examine potential differences that were not anticipated or predicted prior to the study

one-way analysis of variance (one-way ANOVA)

a statistical test that determines whether responses from the different conditions are essentially the same or whether the responses from at least one of the conditions differ from the others.

planned contrasts

statistical tests that examine comparisons between groups that were predicted ahead of time. these tests have the added benefit of allowing the combination of two conditions to be compared to a third.

post-hoc tests

statistical tests that examine all of the possible combinations of conditions in a way that statistically accounts for the fact that not all of them were predicted ahead of time

experimental realism

the degree to which a study participant becomes engrossed in the manipulation and is truly influenced by it

mundane realism

the degree to which a study parallels everyday situations in the rela world.

reliability

the stability or consistency of a measure

validity

the degree to which a tool measures what it claims to measure

sensitivity

the range of data a researcher can gather from a particular instrument

experimental hypothesis

a clear and specific prediction of how the independent variable influences the dependent variable

institutional review board (IRB)

a board that reviews the ethical merit of all the human research conducted within an institution

descriptive study

describes or summarizes what is happening in a meaningful way

inferential study

tests a specific prediction about why something occurs

one-way analysis of variance

if a study has three levels or groups and has a continuous dependent variable, what statistic should you use?

The F score and p level in an ANOVA will only tell you whether ____ ___ ___ ____ ____. To determine which means are different, and the nature or direction of those differences, you need to look at the mean via a ___ ___ test

there is a significant difference, post-hoc