50 terms

the aim of science

is to produce knowledge, to understand and explain some aspect of the world around us.

concepts

abstractions communicated by words or other signs that refer to common properties among phenomena

explanations

are attempts to satisfy curiosity

empirical generalization

a generalization or hypothesis inductively derived from observations

hypothesis

an expected but unconfirmed relationship among two or more variables

theory

a logically interconnected set of propositions that show how or why a relationship occurs

serendipity pattern

unanticipated findings that cannot be interpreted meaningfully in terms of prevailing theories and that give rise to new theories

inductive reasoning

a reasoning in which the conclusion goes beyond the evidence

deductive reasoning

a process of reasoning in which the conclusion necessarily follows if the evidence is true

aggregate data

information about one set of units that is statistically combined to describe a large social unit

variables

characteristics of units that vary, talking on different values, categories, or attributes for different observations

ecological fallacy

when you judge based on one unit of analysis

extraneous variables

all variables other than the independent and dependent variables in a hypothesized relationship.

other units of analysis that spring up between A and B

other units of analysis that spring up between A and B

antecedent variables

occurs prior in time to both the independent and dependent variable.

intervening variable

a variable that is intermediate between two other variables in a casual chain

"affects A and B"

"affects A and B"

quantitative variable

a variable that has categories that express numerical distinctions

qualitative variable

a variable that has has discrete categories, usually designated by words or labels and nonnumerical between categories

positive/direct relationship

a relationship in which an increase in the value of one variable is accompanied by an increase in the value of the other

negative/inverse relationship

a relationship in which an increase in the value of one variable is accompanied by a decrease in the value of the other

conceptualization

the process of formulating and clarifying concepts

operationalization

the detailed description of the research operations or procedures necessary to assign units of analysis to the categories of a variable in order to represent conceptual properties

4 types of measurement

nominal,ordinal,interval,ratio

nominal measurement

a system in which cases are classified into to or more categories on some variable.

creates categories,always exhaustive,mutually exclusive

creates categories,always exhaustive,mutually exclusive

ordinal measurement

numbers indicate the rank order of cases on some variable

ranking,ordering

ranking,ordering

interval measurement

has qualities of the nominal and ordinal levels plus the requirement that distances or intervals between "numbers" represent equal distances in the variable being measured

ratio measurement

includes the features of the other levels plus an absolute (non-arbitrary) zero point

reliability

is concerned with questions of stability and consistency

same results should appear

same results should appear

validity

the congruence or "goodness of fit" between an operational definition and the concept it is purported to measure

"accuracy"

"accuracy"

systematic measurement errors

results from factors that systematically influence either the process of measurement or the concept being measured

(ie. IQ test)

(ie. IQ test)

test re-test method

test the same people several times

split half method

a scale or index is applied once to a sample of cases, after which the items of the scale are divided into halves usually by random selection: each half is then treated as a subtest with the results of two subtests correlated to obtain an estimate of reliability

inter coder reliability

when multiple people use the same measurement

face validity

refers simply to a personal judgement that an operational definition appears,on the face of it,to measure the concept it is intended to measure

"based on what we see, is the instrument valid"

"based on what we see, is the instrument valid"

content validity

concerns the extent to which a measure adequately represents all facets of a concept

"does it cover a wide scope?"

"does it cover a wide scope?"

criterion-related validity

applies to measuring instruments that have been developed for some practical purpose other that testing hypotheses or advancing scientific knowledge

sample

a subset of cases selected from a population

simple random sampling

the basic probability sampling design that is incorporated in all the more elaborate probability sampling designs. (lottery)

stratified random sampling

the population is first subdivided into two or more mutually exclusive segments, called strata, based on categories of one or more combination of relevant variables

cluster sampling

a probability sampling procedure in which the population is broken down into natural groupings or area, called clusters, and a random sample of clusters is drawn

systematic sampling

a probability sampling procedure in which cases are selected from an available list at a fixed interval after after a random start

convenience sampling

based on luck, the people that are present at the moment, accidental

purposive sampling

a form of non probability sampling that involves the careful selection of typical cases that represent relevant dimensions of the population

quota sampling

a form on non probability sampling that involves the allocation of quotas of cases for various strata and the nonrandom selection of cases to fill the quotas

snowball sampling

uses a process of chain referral: when members of the target population are asked to provide names of other members of the target population

exhaustive

the measurement requirement that a measure includes all possible values or attributes of a variable so that every case can be classified

validity

the congruence or "goodness of fit" between an operational definition and the concept it is purported to measure

probability sampling

sampling based on a process of random selection that gives each case in the population an equal or known chance of being included in the sample

non-probability sampling

processes of case selection other than random selection

discriminant validity

the extent to which a measure of a particular concept differentiates that concept from other concepts from which it is intended to differ

mutually exclusive

the measurement requirement that each case can be placed in only one category of a variable