Hindsight bias

the belief that after learning an outcome, one would have foreseen it

Overconfidence

the tendency to be more confident than correct and to overestimate the accuracy of our beliefs and judgements

critical thinking

examines assumptions, discerns hidden values, evaluates evidence, and assesses conclusions

theory

an explanation that organizes observations and predicts behaviors or events

hypothesis

a testable prediction, often implied by a theory

operational definition

a statement used to define research variables

replication

the repetition of research study with different participants in different situations to get other results

case study

an observation technique where one person is studied in depth

survey

a group of questions given to people based on a particular subject to get a range of answers

population

all the cases in a group being studied

random sample

a sample where each person participating has an equal chance of inclusion

naturalistic observation

the observation and recording of behavior in natural situations without manipulation of the situation

correlation

a measure of how two factors may vary together and how well each predicts the other

correlation coefficient

a statistical index of the relationship between two things

scatterplot

a graphed cluster of dots, each represents the value of two variables

illusory correlation

the idea of a relationship where none really exists

experiment

a research method in which an investigator manipulates one or more factors to observe the effect on some behavior or mental process

random assignment

the assignment of participants to experimental and control groups by chance to eliminate bias

double-blind procedure

a procedure in which both the researcher and the participants are unaware about which participants have the treatment or the placebo

placebo effect

experimental results caused by expectations alone

experimental group

the group that is exposed to the treatment

control group

the group that is not exposed to the treatment

independent variable

the experimental factor that is manipulated; the studied variable

confounding variable

a factor other than the independent variable that might produce an effect in an experiment

dependent variable

the outcome factor; the variable that may change in response to manipulations of the independent variable

mode

the most frequently occurring score in data

mean

the average in data

median

the middle score in a distribution

range

the difference between the highest and lowest scores in data

standard deviation

a computed measure of how much scores vary around the mean score

normal curve

a symmetrical, bell-shaped curve that describes the distribution of many types of data

statistical significance

a statistical statement saying how likely it is that a result occurred by chance

culture

behaviors, ideas, attitudes, values and traditions shared by a group of people and transmitted from on generation to the next

informed consent

an ethical principle that research participants are to be told enough to allow them to choose to participate or not

debriefing

the post experimental explanation of a study, including its purpose and any deceptions