Psychology Chapter 1

Descriptive vs. inferential statistics

Descriptive- describe data inferential statistics- try to infer causation between variables. ex: when presenting his findings, the scientist first showed the facts and then explored implications

Histogram

a bar graph that shows the frequency of data using equal intervals ex: when rachel gave her presentation, she used a histogram to prove her point

Scatter plot

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 ex: a correlation between junk food intake and weight can best be examined on a scatter plot

Correlation and correlation coefficients

a measure of the extent to which two factors vary together, and thus of how well either factor predicts the other ex: Mrs. smith's class did an experiment to see if height and grades were realted

Illusory correlation

a perception of a relationship where none exists ex: if Brian believes there is a correlation, he will be able to see one

Experiment: be able to design one

a research method in which an investigator manipulates one or more factors to observe the effect on some behavior or mental process. By randomly assignment of participants, the experimenter aims to control other relevant factors ex: in order to gain accurate results, it is important to use the experimental design

Random sample

a sample that fairly represents a population because each member has an equal chance of inclusion ex: to get more accurate results, phone polls use a random sample

Operational definition

a statement of procedures used to define research variables ex:when comparing class size to test scores, one must use the operational definition

Statistical significance

a statistical statement of how likely it is that an obtained result occurred by chance ex: to see if a correlation matters, you should see if it is statistically significant

Survey

a technique for ascertaining the self-reported attitudes or behaviors of people, usually by questioning a representative, random sample of them ex: because we are a battle ground state, we recieve a large number of phone surveys

Hypothesis

a testable prediction, often implied by a theory ex: the first step to a successful experiment is to create a hypothesis that describes what you will expect to happen

Population

all the cases in a group, from which samples may be drawn for a study ex: the people used in the Milgram experiment were the population

Double-blind procedure

an experimental procedure in which both the research participants and the research staff are ignorant about whether the research participants have received the treatment or a placebo ex: in a drug study, neither the patient nor the doctor knew who was actually recieveing the drug

Theory

an explanation using an integrated set of principles that organizes and predicts observations ex: Global warming is a scientific theory

Case study

an observation technique in which one person is studied in depth in the hope of revealing universal principles. ex:in class, we watched an interview of a family that cared for a feral child, who has become a case study

Random assignment

assigning participants to experimental and control conditions by chance, thus minimizing preexisting differences between those assigned to the different groups ex: in trying to determine who the country will elect this year, pollers must not call only the people that live in short pump

Experimenter bias

expectations by the experimenter that influence the results of an experiment or how it is interpreted ex: an experimentor that believes dolphins can understand english may find evidence that isn't there

Placebo effect

experimental results caused by expectations alone; any effect on behavior caused by the administration of all inert substance or condition, which is assumed to be an active agent, ex: if a doctor believes a patient isn't really in pain, they may give them sugar pills, a placebo

Frequency polygon

graph of a frequency distribution that shows the number of instances of obtained scores, usually with the data points connect by straight lines ex:the frequency polygon showed the student's average test scores throughout the year

Measures of central tendency: mean, median, mode

mode- most frequently occurring scores in a distribution mean- the arithmetic average of a distribution, obtained by adding the scores and then dividing by the number of scores median- the middle score in a distribution, half the scores are above it and half are below it ex: while the mean and median may be observed, Mrs. Stalls is more interested in her class' average or mean score

Naturalistic observation

observing and recording behavior in naturally occurring situations without trying to manipulate and control the situation ex: Jane Goodall used naturalistic observation

Anecdotal evidence

personal stories about specific incidents and experiences. ex: elizabeth used anecdotal evidence by telling her life story to prove that racism still exists

Measures of variability: range and standard deviation

range- the difference between the highest and lowest scores in a distribution standard deviation- a computed measure of how much scores vary around the mean score ex: Range and standard deviation are a good way to analyze data because they aren't ass effected by outlyers

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 ex: in class, we watched a movie who replicated an experiment she originally conducted the year MLK died

Longitudinal study

research in which the same people are restudied and retested over a long period of time in an experiment studying whether kids who have backyard are more active, a longitudinal study is used to study the subjects from age 3 to 15

APA Ethical Principles of Psychologists and Code of Conduct

rules set forth by the APA to which all experimenting psychologists must adhere. ex: if you plan to redo the stanford prison experiment, you may hear from the APA

Control condition

the condition of an experiment that contrasts with the experimental condition and serves as a comparison for evaluating the effect of the treatment ex: in an experiment studying the effects of tai chi on heart health, one group will not do tai chi

Experimental condition

the condition of an experiment that exposes participants to the treatment, that is, to one version of the independent variable ex: in a food tasting experiment, participants are exposed to the food they will evaluate

Independent variable

the experimental factor that is manipulated; the variable whose effect is being studied ex: in an experiment of the effect of drinking milk on weight, milk is the IV

dependent variable

the outcome factor; the variable that may change in response to manipulations of the independent variable ex: in an experiment of the effect of drinking milk on weight, weight is the DV

Hawthorne effect

the tendency for people to behave differently when they know they are being studied ex: a person who normally is outgoing and likes to talk may be more reserved in a laboratory

Hindsight bias

the tendency to believe, after learning an outcome, that one would have foreseen it ex: I knew the right answer was B!

False consensus effect

the tendency to overestimate the extent to which others share our beliefs and behaviors ex: if Julie believes the x factor is the best show ever, she may assume all of her friends also love it

Critical thinking

thinking that does not blindly accept arguments and conclusions, rather it examines assumptions, discerns hidden values, evaluates evidence, and assesses conclusions ex: critical thinking can prove difficult to young students who are used to memorizing facts and repeating them

Confounding variables

variables that have an unwanted influence on an experiment ex: in a study exploring whether kids who read at night with their parents do better in school, the difference in school and teachers may impact the experiment