MHS AP Psychology- Unit 0

Experiment

A way of confirming the validity of psychological findings with consistent and repeatable results

Hypothesis

testable prediction, not yet confirmed or unconfirmed

Operational Definitions

a carefully worded statement of the exact procedures, helps with future replication

Theories

explanations that organize and predict

Experimental Group

the group being tested/exposed; recieves the IV

Control Group

the group NOT being tested/exposed; may receive the placebo; its results compared to experimental group

Independent Variable (IV)

manipulated factor

Dependent Variable (DV)

consistent factor

Random Selection (AKA Random Sample)

a random selection of a diverse population used to eliminate bias; leads to generalizability

Random Assignment

subjects placed in experimental/control groups at random to eliminate bias

Convience Sampling

technique where subjects are chosen based on proximity/accessibility (diminishes integrity)

Confounding Variables

factors that cause differences between the experimental group and the control group other than the IV (age, gender, home life, etc.). Only happens in experiments

Sampling Bias

when a sample is not representative of the population from which it is drawn

Experimenter Bias

when the experimenter (intentionally or unintentionally) influences the results to portray a certain outcome

Social Desirability Bias

the tendency of survey respondents to give socially approved answers to questions about oneself

Correlational Study

study that determines the relationship between 2 variables

Naturalistic Observations

unhindered observations in a natural environment (modern uses may include technology such as apple watches and internet/social media usage)

Case Study

study of one individual in great detail

Meta-Analysis

a procedure for statistically combining the results of many different research studies (nonexperimental method)

Scatterplots

a graphed cluster of dots, each of which represents the values of two variables. The slope of the points suggests the direction of the relationship between the two variables, the amount of scatter suggests the strength of the correlation

Quantitative data/research

Data that is in numbers

Qualitative data/research

Data in the form of words

Correlation Coefficient

measures the relationship strength between 2 variables ranging from -1 to 1

Positive Correlation

A correlation where as one variable increases, the other also increases, or as one decreases so does the other. Both variables move in the same direction.

Negative Correlation

as one variable increases, the other decreases

Positive Skew

mean > median > mode

Negative Skew

mean < median < mode

Bimodal

data set with two peaks

Measures of Central Tendency

the mean, median, and mode of a data set. these represent the typical or common characteristics of a data set

Mode

most frequently occurring score

Mean

average of data set

Median

the middle score in a distribution

Range

the difference between the highest and lowest scores

percentile rank

percentage of scores that fall below a given score

Standard Deviation (SD)

measures the average difference between each score and the mean of the data set

Statistical Significance

a statistical statement of how likely it is that an obtained result occurred by chance (goal is 95%)

Institutional Review Board (IRB)

A committee at each institution where research is conducted to review every experiment for ethics and methodology.

IACUC (Institutional Animal Care and Use Committee)

committee that approves or denies permission for studies involving animals

Experimental Prerequisites

1) Obtain informed consent of the subjects

2) Protection from physical harm or discomfort

3) Confidentiality regarding subject information

4) A full debrief of the results for subjects afterwards

Informed Assent

-case in which child is informed about what is going to be required and they have the opportunity to agree to or disagree to treatment

-children of different ages require different levels of confidentiality

Falsifiable

the possibility that a hypothesized relationship can be shown to be incorrect

Survey

non-experimental method for obtaining the self-reported attitudes or behaviors of a particular group, Wording effect and self reporting can be problematic.

Self-Report Bias

bias when people report their behavior inaccurately

Random Sampling

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

Population

all those in a group being studied, from which samples may be drawn

Variable

anything that can vary and is feasible and ethical to measure

Illusory Correlation

perceiving a relationship where none exists, or perceiving a stronger-than-actual relationship

Regresson Toward the Mean

the tendency for extreme or unusual scores or events to fall back (regress) toward the average

Placebo Effect

the phenomenon in which the expectations of the participants in a study can influence their behavior

Informed Consent

giving potential participants enough information about a study to enable them to choose whether they wish to participate

Debriefing

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

Descriptive Statistics

numerical data used to measure and describe characteristics of groups. Includes measures of central tendency and measures of variation.

Inferential Statistics

numerical data that allow one to generalize- to infer from sample data the probability of something being true of a population

Effect Size

the strength of a relationship between two or more variables

Psychology

the scientific study of behavior and mental processes

Biopsychosocial Perspective

A perspective on psychopathology that emphasizes the biological, psychological, and social factors that contribute to mental illness.

Peer Review

A process by which the procedures and results of an experiment are evaluated by other scientists who are in the same field or who are conducting similar research.

Single-Blind Procedure

research design in which participants don't know whether they are in the experimental or control group

Double-Blind Procedure

an experimental procedure in which both the research participants and the research staff are ignorant (blind) about whether the research participants have received the treatment or a placebo. Commonly used in drug-evaluation studies.

Protection from Harm

the right of research participants to be protected from physical or psychological harm

Confidentiality

the act of holding information in confidence, not to be released to unauthorized individuals

Psychology as a science

uses systematic methods to observe human behavior and draw conclusions

American Psychological Association (APA)

World's largest association of psychologists with around 152,000 members including scientists, educators, clinicians, consultants and students

Experimental Psychologists

the study of behavior and thinking using the experimental method

industrial/organizational psychologist

a psychologist who uses psychological concepts to make the workplace a more satisfying environment for employees and managers

Clinical psychologists

Psychologists who specialize in the diagnosis and treatment of psychological disorders and everyday behavioral problems.

counseling psychologist

A psychologist who specializes in the treatment of milder emotional and behavioral disturbances.

Psychiatrist vs. Psychologist

- can prescribe vs. cannot prescribe

- M.D. vs. M.A, M.S.W, Ph.D, Psy.D, Ed.D

biopsychosocial approach

an integrated perspective that incorporates biological, psychological, and social-cultural levels of analysis to explain human behavior

Replication

repeating the essence of a research study, usually with different participants in different situations, to see whether the basic finding extends to other participants and circumstances

Validity

the extent to which a test measures or predicts what it is supposed to

normal curve (normal distribution)

a symmetrical, bell-shaped curve that describes the distribution of many types of data; most scores fall near the mean (about 68 percent fall within one standard deviation of it) and fewer and fewer near the extremes. (68-95-99.7)

Scientific Method Steps

Theory, Hypothesis, Experiment, Data Collection, Conclusion, If necessary restart

non-experimental research methods

Case studies, surveys, correlational studies, meta-analysis, naturalistic observation

directionality problem

a problem encountered in correlational studies; the researchers find a relationship between two variables, but they cannot determine which variable may have caused changes in the other variable

third variable problem

the concept that a correlation between two variables may stem from both being influenced by some third variable (unknown)

correlation is not causation

just because two variables correlate strongly does not mean that one caused the other, only an experiment with manipulated variables cab determine causation

confederates (in research)

a person who secretly takes part in an experiment as an accomplice to the researcher, pretending to be a subject or participant

structured interview

a research procedure in which all participants are asked to answer the same questions; gathers qualitative data