ap psychology- scientific unit

hypothesis

a testable, educated guess or prediction about a relationship between 2 or more variables

theory

organized set of principles that explains observations and predicts behavior and events

overconfidence 

cognitive bias where individuals confidence is greater than accuracy 

operational definition 

a specific, measurable, and objective description of a psychological concept, outlining exactly how it will be measured in a study

replication

process of repeating a research study to verify findings

case study

in-depth analysis of groups or individuals to try and understand psychological patterns and/or behaviors 

naturalistic observation

research method where subjects are observed in their natural habitats without interference 

survey 

research method used to systematically collect self-reported data

social desirability bias

bias in people answering in a way they think will please researcher

self-reported bias

bias when people report their behavior inaccurately

sampling bias

sample used in a study is not a representation of the larger population being studied 

random sample

sample that represents a population because each member has equal chance of inclusion

population

everyone in a group being studied

correlation

statistical relationship between 2 variables indicating how closely they are associated

correlation coefficient

numerical measurement of the strength and direction of linear relationship between 2 variables

single-blind procedure 

experiment where the participants don't know what group they're in 

double-blind procedure

neither the participants nor the researcher know which group the participants are in

placebo effect

phenomenon where a person experiences a physical/psychological improvement after receiving inactive treatment

confounding variable

factor that affects both independent and dependent variable

experimenter bias

biased caused when researcher may unintentionally influence results to confirm own beliefs 

validity

experiment tests what it is supposed to

quantitative research

collects/analyzes numerical data using statistical analysis to measure variables and determine relationships 

qualitative research

collects and analyzes non-numerical data to understand meanings, experiences, and perspectives 

informed consent

principle that requires researchers to provide participants with enough information to make voluntary and educated decisions about participating in study 

debriefing

providing enough information with a thorough explanation of a research study after their participation is complete

mode

most frequent number in a data set

mean

average of data set

median

middle number of data when scores are arranged from high to low

normal curve

bell-shaped graph that shows dad clustering around average

standard deviation 

how spread out a set of scores is from average

meta-analysis

statistically combining the results of many research studies on same topic to arrive at overall conclusion

statistical significance

measure of how likely it is that the results of a study are due to independent variable and not random chance