chapter 1 pt 2 Flashcards
the tendency to believe, after learning an outcome, that one would have foreseen it
hindsight bias
an explanation using an integrated set of principles that organizes observations and predicts behaviors or events
theory
A testable prediction, often implied by a theory
hypothesis
a carefully worded statement of the exact procedures used in a research study
operational definition
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
replication
a descriptive technique in which one individual or group is studied in depth in the hope of revealing universal principles
case study
a descriptive technique of observing and recording behavior in naturally occurring situations without trying to manipulate and control the situation
naturalistic observation
a flawed sampling process that produces an unrepresentative sample
sampling bias
all those in a group being studied, from which samples may be drawn
population
a sample that fairly represents a population because each member has an equal chance of inclusion
random simple
a measure of the extent to which two factors vary together, and thus of how well either factor predicts the other.
correlation
a statistical index of the relationship between two things (from -1 to +1)
correlation coefficient
anything that can vary and is feasible and ethical to measure
variable
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 variables. The amount of scatter suggests the strength of the correlation.
scatterplot
perception of a relationship where none exists, or perception of a stronger relationship than actually exists
illusory correlation
the tendency for extreme or unusual scores to fall back (regress) toward their average.
regression toward the mean
A research method in which an investigator manipulates one or more factors to observe the effect on some behavior or mental process
experiment
In an experiment, the group that is exposed to the treatment, that is, to one version of the independent variable.
experimental group
In an experiment, the group that is not exposed to the treatment; contrasts with the experimental group and serves as a comparison for evaluating the effect of the treatment.
control group
assigning participants to experimental and control groups by chance, thus minimizing preexisting differences between those assigned to the different groups
random assignment
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.
double blind procedure
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.
placebo
in an experiment, the factor that is manipulated; the variable whose effect is being studied
independent variable
a factor other than the factor being studied that might influence a study’s results
confounding variable
in an experiment, the outcome that is measured; the variable that may change when the independent variable is manipulated
dependent variable
the extent to which a test measures or predicts what it is supposed to
validity
giving potential participants enough information about a study to enable them to choose whether they wish to participate
informed consent
the post-experimental explanation of a study, including its purpose and any deceptions, to its participants
debriefing
numerical data used to measure and describe characteristics of groups. Includes measures of central tendency and measures of variation.
descriptive status
a bar graph depicting a frequency distribution
histogram
the most frequently occurring score(s) in a distribution
mode
the arithmetic average of a distribution, obtained by adding the scores and then dividing by the number of scores
mean
the middle score in a distribution; half the scores are above it and half are below it
median
a representation of scores that lack symmetry around their average value
skewed distribution
the difference between the highest and lowest scores in a distribution
range
a computed measure of how much scores vary around the mean score
standard deviation
the symmetrical bell-shaped curve that describes the distribution of many physical and psychological attributes. Most scores fall near the average, and fewer and fewer scores lie near the extremes.
normal curve
numerical data that allow one to generalize- to infer from sample data the probability of something being true of a population
inferential status
a statistical statement of how likely it is that an obtained result occurred by chance
statistical significance
