Psychology Unit 0

Naming something the '0th' thing doesn't even make sense logically since 0 is to indicate no amount/object/whatever. That's why "0 is a hero" in the "first is the worst second is the best..." rhyme, because heroes(and zeroth things) don't exist.

empirical approach

an evidence based method that draws on observation and experimentation

critical thinking

thinking that does not automatically accept arguments and conclusions. Instead, it examines assumptions, appraises the source, discerns hidden biases, evaluates evidence, and assesses conclusions

hindsight bias

the tendency to believe, after learning an outcome, that one would have foreseen it

peer reviewers

scientific experts who evaluate a research article’s theory, originality, and accuracy

theory

an explanation using an integrated set of principles that organizes observations and predicts behaviors or events

hypothesis

a testable prediction, often implied by a theory

operational definition

a carefully worded statement of the exact procedures used in a research study

replication

repeating the essence of a research study, usually with different participants in different situations to see whether the basic finding can be reproduced

confirmation bias

the tendency to seek out information that supports one position or idea

overconfidence

the tendency to overestimate our knowledge and abilities in a certain area

population

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

sample

a small portion of individual cases selected from a greater population

representative sample

a sample from a larger group that accurately represents the characteristics of a larger population

random sample

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

convenience sample

a non-probability sampling method where units are selected for inclusion because they are the easiest for the researcher to access

sampling bias

the collection of samples that does not accurately represent the entire group since it is not random and tends to produce a particular outcome

experimental bias

the unintentional influence of the experimenter’s expectations, beliefs, or preconceived notions on the outcome of a study or research experiment

social desirability bias

the tendency of survey respondents to answer questions in a manner that will be viewed favorably by others

validity

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

qualitative measurement instruments

a research method that relies on in-depth narrative data that are not translated into numbers

quantitative measurement instruments

a research method that relies on quantifiable, numerical data

experiment

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

independent variable

in an experiment, the factor that’s being manipulated; the variable whose effect is being studied

dependent variable

in an experiment, the outcome that is measured; the variable that may change when the independent variable is manipulated

confounding variable

in an experiment, a factor other than the factor being studied that might influence a study’s results

experimental group

in an experiment, the group exposed to the treatment - that is, to one version of the independent variable

control group

in an experiment, the group not exposed to the treatment; contrasts with the experimental group and serves as a comparison for evaluating the effect of the treatment

random assignment

assigning participants to experimental and control groups by chance, thus minimizing preexisting differences between the different groups

single blind procedure

a type of trial in which only the researcher doing the study knows which treatment or intervention the participant is receiving

double blind procedure

an experiment where both the research participants and the staff are ignorant about whether the participants received the treatment or a placebo

placebo effect

experimental results caused by expectations alone; any effect on behavior caused by the administration of an inert substance or condition, which the recipient assumes is an active agent

case study

a descriptive technique in which one individual or group is studied in depth in the hopes of revealing universal principles

naturalistic observation

a descriptive technique of observing and recording behavior in the naturally occurring situations without trying to manipulate and control the situation

survey

a descriptive technique for obtaining the self reported attitudes or behaviors of a particular group, usually by questioning a representative, random sample of the group

correlation/correlational studies

a measure of the extent to which two factors vary together, and thus of how well either factor predicts the other

correlation coefficient

a statistical index of the relationship between two variables(from -1.00 to +1.00)

illusory correlation

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

scatter plot

a graph in which the values of two variables are plotted along two axes, the pattern revealing any correlation present

regression towards the mean

the tendency for extreme or unusual scores or events to fall back towards the average

statistical concepts

the fundamental elements of statistics

descriptive statistics

numerical data used to measure and describe characteristics of groups; include measures of central tendency and measures of variation

inferential statistics

numerical data that allow one to generalize the probability of something being true of a population

histogram

a bar graph depicting a frequency distribution

central measures of tendency

a single value that attempts to describe a set of data by identifying the central position within that set

mean

the arithmetic average of a distribution, obtained by adding the scores and then dividing the number of scores

median

the middle score of a distribution; half the scores are above it and half are below it

mode

the most frequently occurring score in a distribution

normal curve

a symmetrical bell shaped curve that describes the distribution of many types of data; most scores fall near the mean and fewer and fewer near the extremes

percentage distributions of scores across the curve

68% in the median and the other 32% split about evenly between the two extremes

skewed distribution

a representation of scores that lack symmetry around their average value

bimodal distribution

when there are two frequently occurring scores

range

the difference between the highest and lowest scores in a distribution

percentile rank

the percentage of scores in an individual score’s frequency distribution that are equal to or lower than it

standard deviation

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

meta analysis

a statistical procedure for analyzing the results of multiple studies to reach an overall conclusion

statistical significance

a statistical statement of how likely it is that a result occurred by chance, assuming there is no difference between the populations being studied

effect size

the strength of the relationship between two variables. The larger the effect size, the more one variable can be explained by the other

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