exam 3

Question 1

non probability sampling
a. always produces samples that possess distorted characteristics relative to the population
b. denies the researcher the use of statistical theory to estimate the probability of correct inferences
c. should never be used under any circumstances
d. includes stratified sampling
e. requires the use of sampling frames

Answer 1

b. denies the researcher the use of statistical theory to estimate the probability of correct inferences

Question 2

You are doing research on hospital personnel—orderlies, technicians, nurses, and doctors. You want to be sure you draw a sample that has cases in each of the personnel categories. You want to use probability sampling. An appropriate strategy would be
a. simple random sampling
b. quota sampling
c. cluster sampling
d. stratified sampling
e. accidental sampling

Answer 2

d. stratified sampling

Question 3

Stratifying a population prior to drawing a sample
a. generally occurs when the variables used to stratify are known to be associated with the dependent variable
b. eliminates the need for simple random sampling
c. is most useful for studying a homogeneous population
d. eliminates the need for probability sampling
e. is an alternative systematic sampling

Answer 3

a. generally occurs when the variables used to stratify are known to be associated with the dependent variable

Question 4

The unit about which information is collected and that provides the basis of analysis is called a(n)
a. universe
b. sampling unit
c. unit of analysis
d. sampling frame
e. element

Answer 4

c. unit of analysis

Question 5

A sampling interval of 5 was used to select a sample from a population of 1000. How many elements are to be in the sample?
a. 5
b. 50
c. 100
d. 200
e. 1000

Answer 5

d. 200

Question 6

You want to examine the relationship between family size and family cohesion. You use as your sample all the students in your research methods class. What kind of sampling design are you using?
a. simple random sampling
b. quota sampling
c. snowball sampling
d. stratified sampling
e. convenience

Answer 6

e. convenience

Question 7

Every key element in a list is chosen for inclusion in the sample in
a. simple random sampling
b. systematic sampling
c. disproportionate sampling
d. cluster sampling
e. stratified sampling

Answer 7

b. systematic sampling

Question 8

The standard error tells us how closely the population parameter is clustered around a single sample statistic. (T/F?)

Answer 8

true

Question 9

In a sample stratified by gender, the sampling error on this variable is reduced to zero. (T/F?)

Answer 9

true

Question 10

A confidence interval at the 68% confidence level will be larger than one constructed at the 95% confidence level. (T/F?)

Answer 10

false

Question 11

Generally, the more heterogeneous the population, the more beneficial it is to use stratified sampling. (T/F?)

Answer 11

true

Question 12

Sampling error is reduced through an increase in the sample size and an increased homogeneity of the elements being sampled. (T/F?)

Answer 12

true

Question 13

Kenny performed an experiment on the effects of after‐school educational activities on students’ academic performance. His experimental group involved after‐school educational activities and his control group involved after‐school non‐educational activities. The majority of the children in the control group left the activities. Which source of internal invalidity is reflected?
a. Instrumentation
b. Testing
c. Statistical regression
d. History
e. Attrition

Answer 13

e. Attrition

Question 14

Feminist performed a study in which he introduced a stimulus (longer coffee breaks) and then measured how often employees left early (the dependent variable). No pretests were done. Which design did he use?
a. Solomon four‐group design
b. Double‐blind design
c. Static group comparison
d. One‐shot case study

e. Classical experimental design

Answer 14

d. One‐shot case study

Question 15

Lee selected people with only the highest self‐esteem scores for her experiment on the effects of divorce on self‐esteem. She should be particularly alert to which potential source of internal validity?
a. History
b. Maturation
c. Testing
d. Statistical regression

e. Attrition

Answer 15

d. Statistical regression

Question 16

Dr. Koo did an experiment on children in a classroom. She measured their social anxiety on Monday, randomly assigned half of them to be taught yoga on Wednesday, and measured their social anxiety again on Friday. The half of the children who were not taught yoga are known as the:
a. Independent variable
b. Experimental group
c. Pretest
d. Control group
e. Posttest

Answer 16

d. Control group

Question 17

Dr. Koo did an experiment on children in a classroom. She measured their social anxiety on Monday, randomly assigned half of them to be taught yoga on Wednesday, and measured their social anxiety again on
Friday. Measuring the children’s social anxiety on Friday is the :
a. Independent variable
b. Experimental group
c. Pretest
d. Control group
e. Posttest
f. Dependent variable

g. Posttest and dependent variable

h. Posttest and independent variable

Answer 17

g. Posttest and dependent variable

Question 18

18. The greatest strength of laboratory experiments lies in the ability to examine numerous variables simultaneously (T/F).

Answer 18

false

Question 19

what is the classical experiment

Answer 19

specific way of structuring research:
3 major components
1. independent and dependent variables
- pretesting and posttesting
- experimental and control groups
2. pretest/posttest
- subjects are initially measured in terms of the DV prior to association with IV (pretested)
- following exposed to IV
- remeasures in terms of DV (posttest)
- differences noted between measurements on the DV are attributed to influence of IV
3. experimental and control groups
- experimental: exposed to whatever treatment, policy, initiative we are testing
- control group: very similar to experimental group, except that they are NOT exposed
- if we see a difference, we want to make sure it is due to the IV, and not to a difference the two groups

Question 20

how do we use independent and dependent variables

Answer 20

• pretesting and posttesting
• experimental and control groups

Question 21

traditional use of experimental and control groups

Answer 21

• experimental: exposed to whatever treatment, policy, initiative we are testing
• control group: very similar to experimental group, except that they are NOT exposed

Question 22

randomization in subject selection

Answer 22

• insures that the experimental and control groups are alike in every way (except for the intervention)

Question 23

instrumentation (threat to internal)

Answer 23

changes in measurement process

Question 24

testing (threat to internal)

Answer 24

subject reactions to testing (retesting) itself

Question 25

maturation (threat to internal)

Answer 25

subject changes/grows during course of study

Question 26

selection bias (threat to internal)

Answer 26

lack of randomization - to assignment or subject -the way the subject are chosen

Question 27

statistical regression to the mean (threat to internal)

Answer 27

natural return to the average

Question 28

experimental mortality (threat to internal)

Answer 28

attrition Participants frequently drop out of experiments whilst they are taking place/before they finish; something that is known as experimental mortality (or experimental attrition).

Question 29

history of (threat to internal validity)

Answer 29

unpredicatable/ external events may occur during the course of the experiment affecting DV

Question 30

internal validity

Answer 30

- potential for rival factors threats: - history - maturation - testing - instrumentation - statistical regression - selection bias - experimental mortality - causal time order

Question 31

external validity

Answer 31

- ask the question of whether findings from the current study apply to other populations, times and or other geographic areas -issue of generalizability - for experiments under heavily controlled conditions rather than natural conditions (reduces internal threats)

Question 32

construct validity

Answer 32

- asks the question of how well the experiment reflects the causal process In reality - an issue of generalizability - can we generalize from this finding in spite of specific measurement concerns

Question 33

statistical conclusion

Answer 33

- ask the question is the N big enough to support stats (associations)

Question 34

quasi experimental design factors

Answer 34

- when randomization is not possible - quasi = "to a certain degree"

Question 35

uses of experiments in cj

Question 36

written documents

Answer 36

prior criminal record - usually see else (besides researcher) collects it for another purpose - product of direct observation or survey

Question 37

diret observation

Answer 37

no interaction with subjects

Question 38

survey

Answer 38

ask questions (includes focus group) many times indirect measures direct interaction with subjects

Question 39

what are the three ways if collecting data

Answer 39

asking questions, direct observation and examining written records.

Question 40

what does the purpose of the research dictate

Answer 40

decisions abut data collection

Question 41

what does probability sampling do for the researcher?

Answer 41

helps generalize back to the pop of unobserved cases

Question 42

probability smapling

Answer 42

each unit in the population has a known chance of selection into the sample - makes it possible for us to make predictions about the larger unobserved population based on the sample

Question 43

what does sampling mean?

Answer 43

1. selecting units from population to represent that entire pop 2. we generalize our finding not only too smaple but entire pop

Question 44

what is a representative sample ?

Answer 44

sample means that the aggregate characteristics of the sample closely approximate those same aggregate characteristics in the population

Question 45

sample statistic

Answer 45

summary description of given variable in a sample; we use sample statistics to make estimates or inferences of population parameters

Question 46

population parameter

Answer 46

summary description of given variable in a population ex. Median income of student: 10,000

Question 47

population

Answer 47

specified grouping of study element; whole group ex. csuf student

Question 48

sampling frame

Answer 48

list of sampling elements in the population (actual list of units to be selected) - names of all 400,000 students

Question 49

sample element

Answer 49

unit about which info is collected and provides for the basis of the analysis; who or what we are studying ex. student

Question 50

what are the advantages of probability pf selection method

Answer 50

1. minimizes bias of sample 2. allows us to estimate the representativeness of the sample to the population

Question 51

do we want our sample to be homogenous or heterogeneous ?

Answer 51

heterogeneous; we are a society that differs in races

Question 52

what is a biased sample

Answer 52

sample mens that the sample is not typical of the pop that it is claimed to represent

Question 53

posttest

Answer 53

an assessment carried out after the application of some intervention, treatment, or other condition to measure any changes that have occurred.

Question 54

pretest

Answer 54

tested on members of target population/study population, to evaluate the reliability and validity of the survey instruments prior to their final distribution.

Question 55

examples of conscious sampling bias

Answer 55

Presidential election voters. If you poll 1000 middle-class, blue collar voters, the sample will be heavily biased because it won't be diverse enough to paint the whole picture.

Question 56

what is the basic principle of probability sampling

Answer 56

all members of the population have an equal chance of being selected for the sample

Question 57

what is a sample distribution

Answer 57

range of sample statistics obtained from many samples.

Question 58

what is a bell shaped curve

Answer 58

- bell curve is a symmetric curve centered around the mean or average of all the data points being measured - set of chosen values across a specified group that tend to have a central, normal values, as peak with low and high extremes tapering off relatively symmetrically on either side

Question 59

what is a normal curve

Answer 59

- symmetrical bell shaped curve repressing the probability density function of a normal distribution

Question 60

what is the roll of standard error

Answer 60

used to estimate the efficiency, accuracy and consistency of a sample

Question 61

standard error

Answer 61

a measure of sampling error; we can estimate the degree to be expected -indicates how closely the sample estimate reflects the population parameter

Question 62

how do you decrease the presence of standard error

Answer 62

- having a large sample size, decreases sample error

Question 63

what are confidence intervals and how are they important

Answer 63

confidence lvs: express the accuracy of our sample statistics in terms of lv of confidence that stats fall in confidence intervals: what the statistics fall within the specified interval from the parameter

Question 64

99% confidence

Answer 64

+ or - 3 standard error

Question 65

95% confidence

Answer 65

+ or - 2 standard error

Question 66

68% confidence interval

Answer 66

+ or - 1 standard error

Question 67

snowball sample

Answer 67

- (non prob) - contact of an initial subject to informant who will then refer other subjects pr informants - done often with criminals, subcultures, hard to reach and hidden populations ex. study of persistent thieves. have contact of several thieves and use them to gain access to several more

Question 68

convenience sample

Answer 68

- non prob - researcher selects sample based on convenience ex. csuf stop and ask to answer questions

Question 69

purposive

Answer 69

- non prob - researcher or another "expert" selects the sample elements done based on some type of criteria or characteristics based on purpose of study ex. study of gang behavior in prison - select 3 of 7 possible gangs be they perform certain characteristics

Question 70

non probability designs

Answer 70

1. purpose or judgement sample 2. convenience 3. Snowball

Question 71

disproportionate stratifed

Answer 71

- probability - purpose of sampling technique is to ensure that sample has higher rep of sample elements based on arable of interest -when a characteristic of pop is not that common - sample is purposefully created to include more of the unusual characteristics ex . large supermarket may account for 20% of all grocery stores but account for 80% of grocery sales - need a disportioncate sample to represent the large supermarket to reflect the 80% rather than number of stores

Question 72

stratified sampling

Answer 72

- probability - can lower standard error - you select certain # from homogenous subsets from pop sample is stratified on certain variable and represent of variable in sample will be improved - ex race, gender, age ex freshman, sophomore, junior , senior, grad + 40,000 students - choosing someone from each category to get the right representative - grouping from each one lowers the probability of standard error

Question 73

systematic sample

Answer 73

- probability - no attached to # only the "list" - ex of 40,000 students - just uses the order of list - every 2nd element Cody Alex + jody Adrain + and so on - however may be a problem with certain characteristic such as ethnicity or alphabet order ex: will always get black Hispanic white black + hispanic white black +

Question 74

simple random

Answer 74

- there is first sampling Frame on this a # is assigned of list ex. 40,00 students *listing each name of student* - then assign numbers and randomly select the sample from the list

Question 75

what are the different types of probability sampling designs

Answer 75

1. simple random 2. systematic random 3. stratified 4. disproportioate

Question 76

what is the difference between sampling designs used by the National Crime Vic Survey and British Crime Survey

Answer 76

the NCVS relies on a sample rather than a census of the entire U.S. population, weights

Question 77

difference between probability and non probability sampling techniques

Answer 77

- probability each unit in the pop has a known chance of selection into the sample; involving random selection - non random selection baed on convince or other criteria; main purpose is to collect data easy

Question 78

ambiguous causal time order

Answer 78

the dependent variable actually caused the change in the stimulus

Question 79

experimental mortality (threat to internal)

Answer 79

attrition Participants frequently drop out of experiments whilst they are taking place/before they finish;

Question 80

sample statistic

Answer 80

summary description of given variable in a sample; we use sample statistics to make estimates or inferences of population parameters

Question 81

sample statistic

Answer 81

summary description of given variable in a sample; we use sample statistics to make estimates or inferences of population parameters

Question 82

posttest

Answer 82

tested on members of target population/study population, to evaluate the reliability and validity of the survey instruments prior to their final distribution.