exam 3 Flashcards
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
b. denies the researcher the use of statistical theory to estimate the probability of correct inferences
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
d. stratified sampling
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
a. generally occurs when the variables used to stratify are known to be associated with the dependent variable
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
c. unit of analysis
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
d. 200
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
e. convenience
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
b. systematic sampling
The standard error tells us how closely the population parameter is clustered around a single sample statistic. (T/F?)
true
In a sample stratified by gender, the sampling error on this variable is reduced to zero. (T/F?)
true
A confidence interval at the 68% confidence level will be larger than one constructed at the 95% confidence level. (T/F?)
false
Generally, the more heterogeneous the population, the more beneficial it is to use stratified sampling. (T/F?)
true
Sampling error is reduced through an increase in the sample size and an increased homogeneity of the elements being sampled. (T/F?)
true
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
e. Attrition
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
d. One‐shot case study
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
d. Statistical regression
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
d. Control group
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
g. Posttest and dependent variable
- The greatest strength of laboratory experiments lies in the ability to examine numerous variables simultaneously (T/F).
false
what is the classical experiment
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
how do we use independent and dependent variables
- pretesting and posttesting
- experimental and control groups
traditional use of 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
randomization in subject selection
- insures that the experimental and control groups are alike in every way (except for the intervention)
instrumentation (threat to internal)
changes in measurement process
testing (threat to internal)
subject reactions to testing (retesting) itself
maturation (threat to internal)
subject changes/grows during course of study
selection bias (threat to internal)
lack of randomization
- to assignment or subject
-the way the subject are chosen
statistical regression to the mean (threat to internal)
natural return to the average
experimental mortality (threat to internal)
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).
history of (threat to internal validity)
unpredicatable/ external events may occur during the course of the experiment affecting DV
internal validity
- potential for rival factors
threats: - history
- maturation
- testing
- instrumentation
- statistical regression
- selection bias
- experimental mortality
- causal time order
external validity
- 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)
construct validity
- 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