The Basics of Social Research Chapters 6 and 7

What factors are contained in the formula for determining sampling error?

the parameter, the sample size, and the standard error.

What is a synonym of purposive sampling?

Judgmental sampling

What are types of probability sampling?

EPSEM, PPS, simple random sampling, and systematic sampling

Thurstone scale

A type of composite measure, constructed in accordance with the weights assigned by "judges" to various indicators of some variables.

What are examples of scales?

- Bogardus social distance - Guttman - Likert - Thurstone

What are the types of scaling techniques?

- Borgardus social distance - Thurstone - Likert - Guttman

Is typology more effective used as independent or dependent variables? Why?

- Independent variables - Interpretation is difficult when they are used as dependent variables.

What is the procedure to produce a simple random sampling?

- 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

How are indexes and scales similar and different?

- intended as ordinal measures of variables - Scales typically satisfy this intention better than do indexes.

What is an example of Guttman scale?

1. Do you drink alcohol? 2. Do you smoke marijuana? 3. Do you use cocaine? One might anticipate that all persons who answer "yes" to #3 would also answer "yes" to #1 ans #2, and so forth.

Index

A type of composite measure that summarizes and rank-orders several specific observations and represents some more-general dimension.

Guttman scale

A type of composite measure used to summarize several discrete observations and to represent some more-general variable.

Bogardus Social Distance Scale

A measurement technique for determining the willingness of people to participate in social relations--of varying degrees of closeness--with other kinds of people.

Cluster sampling

A multistage sampling in which natural groups are sampled initially, with the members of each selected group being subsampled afterward.

Snowball Sampling

A nonprobability-sampling method, often employed in field research, whereby each person interviewed may be asked to suggest additional people for interviewing.

Semantic Differential

A questionnaire format in which the respondent is asked to rate something in terms of two, opposite adjectives, using qualifiers such as "very," "somewhat," "neither," "somewhat," and "very" to bridge the distance between the two opposites.

EPSEM

A sample design in which each member of a population has the same chance of being selected into the sample.

Random Selection

A sampling method in which each element has an equal chance of selection independent of any other event in the selection process.

Scale

A type of composite measure composed of several items that have a logical or empirical structure among them.

Likert Scale

A type of composite measure developed by Rensis Likert in an attempt to improve the levels of measurement in social research through the use of standardized response categories in survey questionnaires to determine the relative intensity of different items.

Purposive sampling

A type of nonprobability sampling in which the units to be observed are selected on the basis of the researcher's judgment about which ones will be the most useful or representative.

Quota Sampling

A type of nonprobability sampling in which units are selected into a 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.

Systematic Sampling

A type of probability sampling in which every kth unit in a list is selected in the sample--for example, every 25th student in the college directory.

Simple Random sampling

A type of probability sampling in which the units composing a population are assigned numbers.

How often are there some degrees of sampling error?

Always

Item Analysis

An assessment of whether each of the items included in a composite measure makes an independent contribution or merely duplicates the contribution of other items in the measure.

Statistic

An estimate of a parameter, derived from a sample study

Weighting

Assigning different weights to cases that were selected into a sample with different probabilities of selection.

Nonprobability sampling

Any technique in which samples are selected in some way not suggested by probability theory.

What are sample questions that you would see using a Bogardus social distance scale?

Are you willing to let international students study at your university? Are you willing to let international students live on campus? Are you willing to let international students live in the same dorm as you? Are you willing to have an international student as your dorm roommate?

How is representativeness enhanced?

By probability sampling and provides for generalizability and the use of inferential statistics.

How does stratification improve the representativeness of a sample?

By reducing the degree of sampling error.

How are the Bogardus social distance scale indicators structured?

By their differences in intensity.

What kind of problems do probability sampling counter?

Conscious and subconscious sampling bias by giving each element in the population a known probability of selection.

What happens in the simplest scenario of weighting?

Each case is given a weight equal to the inverse of its probability of selection.

What does the criteria of item selection include?

Face validity, unidimensionality, the degree of specificity with which a dimension is to be measured, and the amount of variance provided by the items.

What is the most popular scaling technique in social research today?

Guttman

What is an example of external validation?

If the index really measures prejudice, it should correlate with other indicators of prejudice.

How is Semantic differential scale different from other formats?

It has more rigor and structure

What is essential for a sampling frame to do when being representative of the population?

It is essential that the sampling frame include all members of the population.

How is the expected error in a sample expressed?

In terms of confidence levels and confidence intervals

How doe stratification improve the representativeness of a sample?

In terms of variables used for stratification

What must researchers do since probability sampling always carries a risk of error?

Inform readers of any errors that might make results misleading

Are statistical techniques always better than nonprobability techniques?

No

How can social researchers selected observations that will allow them to generalize to people and events not observed?

Often this involves sampling

Why is Bogardus Social Distance Scale efficient?

One can summarize several discrete answers without losing any of the original details of the date.

Which sampling methods makes it possible to estimate the amount of sampling error expected in a given sample?

Probability sampling methods

What is often a key element in probability sampling?

Random selection

What are examples of nonprobability sampling?

Reliance on available subjects as well as purposive, snowball, and quota sampling.

What are informants not to be confused with?

Respondents

What are the principal steps in constructing an index?

Selecting possible items, examining their empirical relationships, scoring the index, and validating it.

What can stratification be combined with?

Simple random, systematic, or cluster sampling

Informant

Someone who is well versed in the social phenomenon that you wish to study and who is willing to tell you what he or she knows about it.

What kind of data does semantic differential scale produce?

Suitable for both indexing and scaling

What are Likert items?

Using such response categories as "strongly agree," "agree," "disagree," and "strongly disagree."

Study population

That aggregation of elements from which a sample is actually selected.

Sampling unit

That element or set of elements considered for selection in some stage of sampling.

Sampling frame

That list or quasi list of units composing a population from which a sample is selected.

Representativeness

That quality of a sample of having the same distribution of characteristics as the population from which it was selected.

What can't nonprobability sampling ensure?

That the resulting sample will be representative of the population being sampled.

Element

That unit of which a population is composed and which is selected in a sample.

What is an expample of typology?

The classification of newspapers as liberal-urban, liberal-rural, conservative-urban, or conservative-rural.

Typology

The classification of observations in terms of their attributes on two or more variables.

Sampling error

The degree of error to be expected in probability sampling.

Confidence Level

The estimated probability that a population parameter lies within a given confidence interval.

Probability Sampling

The general term for samples selected in accordance with probability theory, typically involving some random-selection mechanism.

Can Likert scale items be used in the construction of other types of composite measures?

Yes

Stratification

The grouping of the units composing a population into homogeneous groups before sampling.

External Validation

The process of testing the validity of a measure, such as an index or scale, by examining its relationship to other presumed indicators of the same variable.

Sampling ratio

The proportion of elements in the population that are selected to be in a sample.

Confidence interval

The range of values within which a population parameter is estimated to lie.

Sampling interval

The standard distance between elements selected from a population for a sample.

Parameter

The summary description of a given variable in a population.

Population

The theoretically specified aggregation of the elements in a study

If different items are indeed indicators of the same variable, should they be related empirically to one another?

Yes

PPS

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 number of units to be subsampled.

What is an example of confidence level?

Thus, we might be 95 percent confident that between 35 and 45 percent of all voters favor Candidate A.

How are elements different from units of analysis?

Units of analysis are used in data analysis

How can items be used in an index in spite of missing data.

Various techniques

When is weighting not necessary?

When all cases have the same chance of selection.

When do researchers need to examine bivariate and multivariate relationships among the items?

When constructing an index

What is an example of cluster sampling?

You might select a sample of U.S. colleges and universities from a directory, get lists of the students at all the selected schools, then draw samples of students from each.