ap psych unit 0

overconfidence

tendency to overestimate abilities

hindsight bias

tendency to believe, after learning an outcome, that one would have foreseen it (I knew it all along)

scientific method

scientists form hypotheses from theories, conduct research, & refine theories in light of research observations

hypothesis

testable prediction for research

theory

hypothesis that has been tested & evaluated many times and is accepted as fact

replication

repeating study to see if the basic finding extends to other participants in other circumstances

falsifiability

belief that for any hypothesis to have credence, it must be inherently disprovable before it can become accepted as a hypothesis

null hypothesis

states there is no relationship between the variables studied (meant to counterbalance hypothesis)

peer review

process that takes place before a study is published to check quality & validity of research and make sure it contributes to its field

meta-analysis

procedure for statistically combining the results of many different studies

descriptive methods

describe behaviors/attitudes but do not explain them; case studies, surveys, & naturalistic observations

case study

an observation technique in which one person is studied in depth to try to reveal universal principles (ex: feral children)

survey

ascertains self-reported attitudes or behaviors of people, usually by using representative, random sample

generalization

can be applied to entire population if survey is representative & random

Likert scale

rating scale for attitude or opinion

self-report bias

when researchers rely on asking people to describe thoughts/feelings/behaviors instead of measuring directly or objectively

social-desirability bias

tendency to give socially approved answers to questions instead

convenience sampling

selecting sample that is not random or systematic but governed by chance/availability (ex: interviewing people exiting a specific store)

sampling bias

collection of samples that do not accurately represent the entire population

naturalistic observation

recording behavior in naturally occurring situations without trying to manipulate & control the situation (ex: observing animals in the wild)

time sampling

taking records at different intervals of time in naturalistic observation

situation sampling

recording behavior in a variety of different situations/settings in naturalistic observation

correlational

measure of how two variables relate to each other and how well each factor predicts the other

scatterplots

graphed cluster of dots, each of which represents values of two variables

positive correlation

two variables rise together

negative correlation

two variables relate inversely to one another; one rises, the other falls

no/zero correlation

two variables do not seem to be related

correlation coefficient

numerical measure of strength of linear relationship between two variables; 0 is no correlation, 1 is perfect; represented as r = +/- ___

effect size

tells you how meaningful relationship between variables or difference between groups is

illusory correlation

perceiving a relationship between variables (usually people, events, or behaviors) even when no relationship exists (ex: weather & joints aching)

directionality problem

it is known that two variables are related, but it is not clear which is cause & which is effect

third variable problem

when a third variable leads to mistaken causal relationship between two variables (ex: correlation between ice cream sales & shark attacks, with 3rd variable being warm weather)

experimental method

an investigator manipulates one or more factors to observe the effect it has on a behavior/mental process

variable

anything that can change or be changed within an experiment

independent variable (IV)

variable being manipulated

dependent variable (DV)

outcome being studied as a result of the independent variable

operational definition

specific & measurable definition of independent & dependent variables; purpose is for experiment to be able to be repeated

experimental group/condition

participants receiving/impacted by the independent variable

control group/condition

participants NOT exposed to the independent variable

random assignment

process whereby all participants have an equal chance of assignment to any condition/group

placebo

substance or treatment that has no effect besides a person's belief in it

placebo effect

person receiving placebo may report positive effects due to belief in drug/treatment

single blind procedure

participants do not know which group they're in

double blind procedure

neither participants nor researchers know who is in which group

experimenter bias

scientists performing research unconsciously influence results to portray a certain outcome

confounding variable

third variable that influences independent & dependent variables

qualitative measures

non-numerical data that helps understand concepts or opinions (dialogue, body language, etc)

quantitative measures

numerical data

institutional review board (IRB)

reviews research studies involving humans for ethics violations

institutional animal care & use committee (IACUC)

reviews research studies involving animals for ethics violations

informed consent

participants are given info about the experiment & allowed to decide if they want to participate; must disclose risks associated with participation

informed assent

people under the age of 18 or who cannot give consent can participate if a parent/legal guardian consents on their behalf

confederate

aide of experimenter who poses as a participant but whose behavior is rehearsed prior to the experiment (allows researchers to reliably capture naive reactions)

debrief

explain what was done and why in the experiment to participants after it happens

measures of central tendency

typical value that represents the whole set of data (mean, median, mode)

mean

average value in a set

median

middle value in a set

mode

most frequent value in a set

frequency distribution

bell curve; list or display of data on a scale of measurement

normal curve

distribution where mean, median, & mode are the same

regression toward the mean

tendency for extremely high or low scores to even out upon retesting

skewness

measure of asymmetry in distribution; outlying data points exist; mean differs from median & frequency distribution isn't a good indicator of data; the way you ski is the way you skew

bimodal distribution

two modes/curves (ex: plotting heights in males & females)

measures in variation

measures of how a data set is spread out (range, standard deviation)

range

difference between the highest & lowest value in a set; shows dispersion

standard deviation

degree to which values differ from each other & vary around the mean value for a set; between 0 & 1/2 of range (closer to 0, closer together values are)

In a normal curve, what percent of data falls within 1 standard deviation?

68%

In a normal curve, what percent of data falls within 2 standard deviations?

95%

In a normal curve, what percent of data falls within 3 standard deviations?

99.7%

statistical significance

statement of how likely it is that the obtained result occurred by chance (uses a formula that is impacted by effect size)

defensible claim

evidence-based argument

refute

to prove wrong by argument or evidence