Types of measure
This is a variable whose attributes have only the characteristics of exhaustiveness & mutual exclusiveness. An example is gender.
That quality of an indicator that makes it seem a reasonable measure of some variable
Face validity
Bogardus social distance scale
This is a type of non probability sampling in which the units to be observed are selected on the basis of the researcher’s judgement about which ones will be the most useful or representative
Purposive (judgemental) sampling
This is a type of probability sampling in which the units composing a population are assigned numbers. A set of random numbers is then generated, & the units having those numbers are included in the sample.
Simple random sampling (SRS)
This is a level of measurement describing a variable with attributes we can rank-order along some dimension.
Ordinal measure
The degree to which a measure relates to some external criterion. Example: validity of college board tests is shown in their ability to predict the success of college students
Criterion-related validity
This is a type of composite measure, constructed in accord with the weights assigned by “judges” to various indicators of some variables
Thurstone scale
This nonprobability sampling method is often employed in field research, whereby each person interviewed may be asked to suggest additional people for interviewing
Snowball sampling
This is a type of probability sampling in which every kth unit in a list is selected for inclusion in the sample. You compute k by dividing the size of the population by the desired sample size; k = the sampling interval. Typically, the first unit is selected at random.
Systematic sampling
This level of measurement describes a variable whose attributes are rank-ordered & have equal distance between adjacent attributes
Interval measure
The degree to which a measure relates to other variables as expected within a system of theoretical relationships
Construct validity
This is a composite measure developed in an attempt to improve the levels of measurement in social research through the use of standardized categories in survey questionnaires, to determine relative intensity of different items. Most frequently used.
Likert scale
This nonprobability sampling method selects units into the sample on the basis of prespecified characteristics, so that the total sample will have the same distribution of characteristics assumed to exist in the population being studied
Quota sampling
The grouping of units composing a population into homogenous groups (or strata) before sampling. May be used w/ SRS, systematic, or cluster sampling. Improves the representativeness of the sample, at least in terms of the stratification variables
Stratification
This level of measurement describes a variable with attributes that have all the qualities of nominal, ordinal, & interval & are also based on a “true zero” point
Ratio measure
The degree to which a measure covers the range of meanings included within a concept
Content validity
This is a questionnaire format in which the respondent is asked to rate something in terms of two, opposite adjectives (e.g. rate books as “boring” or “exciting”) using qualifiers such as “very”, “somewhat”, “neither”, “somewhat”, & “very” to bridge the distance between the two opposites
Semantic differential
A method for a sample design in which each member of a population has the same change of being selected into the sample
Equal probability of selection method (EPSEM)
A multistage sampling in which natural groups are sampled initially, with the members of each selected group being subsampled afterward
Cluster sampling
All variables must have these two qualities
Controlling more variables, improving measurement technique, increasing randomization, blinding the experiment group, or adding a control/placebo group are all examples of what?
Increasing and improving validity
This is a type of composite measure used to summarize several discrete observations & to represent some more-general variable
Guttman scale
This is a sampling method in which each element has an equal chance of selection independent of any other event in the selection process
Random selection
This refers to a type of multistage cluster sample in which clusters are selected, not with equal probabilities, but with probabilities proportionate to their sizes — as measured by the # of units to be subsampled
Probability proportionate to size (PPS)