Chapter 6

Question 1

Central limit theorem

Answer 1

A lawlike mathematical relationship that states whenever many random samples are drawn from a population and plotted, a normal distribution is formed, and the centre of such a distribution for a variable is equal to its population parameter

Question 2

Cluster sampling

Answer 2

A type of random sampling that uses multiple stages and is often sued to used to cover wide geographic areas in which aggregated units are randomly selected then samples are drawn from the sampled aggregated units, or clusters

Question 3

Confidence interval

Answer 3

A range of values, usually a little higher and lower than a specific value found in a sample, within which a researcher has a specified and high degree of confidence that the population parameter lies.

Question 4

Conviencience sampling

Answer 4

A type of nonrandom sample in which the researcher selects anyone he or she happens to come across.

Question 5

Deviant case sampling

Answer 5

A type of nonrandom sample, especially used by qualitative researchers, in which a researcher selects unusual or nonconforming cases purposely as a way to provide greater insight into social processes or a setting.

Question 6

Hidden populations

Answer 6

People who engage in clandestine, deviant, or concealed activities and who are difficult to locate and study

Question 7

Inferential statistics

Answer 7

A branch of applied mathematics or statistics based on a random sample. It lets a researcher make precise statements about the level of confidence he or she has in the results of a sample being equal to the population parameter.

Question 8

Nonrandom sample

Answer 8

A type of sample in which the sampling elements are selected using something other han a mathematically random process

Question 9

Parameter

Answer 9

A characteristic of the entire population that is estimated from a sample

Question 10

Population

Answer 10

The name for the large general group of many cases from which a researcher draws a sample and which is usually stated in theoretical terms

Question 11

Probability proportionate to size (PPS)

Answer 11

An adjustment made in cluster sampling when each cluster does not have the same number of sampling elements.

Question 12

Purposive sampling

Answer 12

A type of nonrandom sample in which the researcher uses a wide range of methods to locate all possible cases of a highly specific and difficult-to-reach population.

Question 13

Quota sampling

Answer 13

A type of nonrandom sample in which the researcher first identifies general categories into which cases or people will be selected, then he or she selects a predetermined number of cases in each category.

Question 14

Random-digit dialling (RDD)

Answer 14

A method of randomly selecting cases for telephone interviews that uses all possivle telephone numbers as a sampling frame

Question 15

Random-number table

Answer 15

A list of numbers that has no pattern in them and that is used to create a random process for selecting cases and other randomization purposes

Question 16

Random sample

Answer 16

A type of sample in which the researcher uses a random number table or similar mathematical random process so that each sampling element in the population will have an equal probaility of being selected

Question 17

Sample

Answer 17

A smaller set of cases a researcher selects from a larger pool and generalizes to the population

Question 18

Sampling distribution

Answer 18

A distribution created by drawing many random samples from the same population

Question 19

Sampling element

Answer 19

The name for a case or single unit to be selected

Question 20

Sampling error

Answer 20

How much a sdample deviates from being representative of the population

Question 21

Sampling frame

Answer 21

A list of cases in a population, or the best approximation of it

Question 22

Sampling interval

Answer 22

The inverse of the sampling ratio, which is used in systematic sampling select cases

Question 23

Sampling ratio

Answer 23

The number of cases in the sample divided by the number of cases in the population or the sampling frame, or the proportion of the population in the sample

Question 24

Sequential sampling

Answer 24

A type of nonrandom sample in which a researcher tries to find as many relevant cases as possible, until time, financiel resources, or his or her energy are exhausted, or until there is no new information or diversity from the cases

Question 25

Simple random sampling

Answer 25

A type of random sample in which a researcher creates a sampling frame and used a pure random process to select cases. Each sampling element in the population will have an equal probability of being selected

Question 26

Snowball sampling

Answer 26

A type of nonrandom sample in which the researcher begins with one case, then, based on information about interrelationships from the case, identifies other cases and then repeats the process again and again

Question 26

Sociogram

Answer 26

A diagram or “map” that shows the network of social relationships, influence patters, or communication paths among a group of people or units

Question 27

Statistic

Answer 27

A numerical estimate of a population parameter computed from a sample

Question 28

Stratified Sampling

Answer 28

A type of random sample in which the researcher first identifies a set of mutually exclusive and exhaustive categories, then uses a random selection method to select cases for each category

Question 29

Systematic sampling

Answer 29

A type of random sample in which a researcher selects every kth. case in the sampling frame using a sampling interval

Question 30

Target population

Answer 30

The name for the large general group of many cases from which a sample is drawn and which is specified in very concrete terms