Midterm #2

Question 1

Target population

Answer 1

defined by researcher’s specific interests

Question 2

Accessible population

Answer 2

Portion of population who are accessible to be recruited for the study

Question 3

Sample population

Answer 3

relatively smaller group of individuals who participate in the study

Question 4

Simple random sampling (random)

Answer 4

• Randomly select participants from list containing total population
• Each individual has equal and independent chance of selection

Question 5

Systematic sampling (random)

Answer 5

• Select every nth participant from list containing total population after random start

Question 6

Stratified random sampling (random)

Answer 6

• Divide population into subgroups and randomly select equal numbers from each subgroup

Question 7

Proportionate stratified random sampling (random)

Answer 7

• Divide population into subgroups and randomly select from each subgroup so proportions in sample correspond to proportions in population

Question 8

Cluster sampling (random)

Answer 8

• Randomly select clusters from a list of all the clusters in the population

Question 9

Convenience sampling (nonrandom)

Answer 9

• Select individual participants who are easy to get

Question 10

Quota sampling (nonrandom)

Answer 10

• Identify subgroups to be included, then establish quotas for individuals to be selected through covenience

Question 11

Descriptive

Answer 11

Intended to answer questions about the current state of individual variables for a specific group of individuals. (Describe specific characteristics of a specific group of individuals)

Question 12

Correlational

Answer 12

• Measure two variables of interest for each individual

- Look at data graphically - scatterplot

Question 13

Experimental

Answer 13

• Intended to answer cause-effect questions about the relationship between variables
• rigorous control to help ensure an unambiguous demonstration of the cause-effect relationship

Question 14

Quasi-experimental

Answer 14

• Attempts to answer cause-effect questions about relationship between two variables, but answers tend to be ambiguous.

Question 15

Nonexperimental

Answer 15

• Demonstrates relationship between variables without explaining relationship.
• Does not use rigour and control or produce cause-effect explanations.

Question 16

External validity

Answer 16

• The extent to which the results obtained in a research study can hold true outside that specific study.

Question 17

Internal validity

Answer 17

• Changes in one variable are followed by changes in another variable and no other variable provides an alternative explanation for the results.

Question 18

Experimenter bias (threat to validity)

Answer 18

• the findings of the of a study are influenced by the experimenter’s expectations or personal beliefs about the study’s outcome.

Question 19

Reactivity (threat to validity)

Answer 19

• participants modify their natural behaviour in response to the fact that they are aware they are being studied
• behaviour can change by being overly cooperative or defensive/uncooperative.

Question 20

Confounding variable (threats to validity)

Answer 20

• extraneous variable (usually unmonitored)
• changes systematically along with the two variables being studied.
• alternative explanation for observed relationships between the two variables.

Question 21

Assignment bias (threats to validity)

Answer 21

Occurs when the process used to assign different participants to different treatments produces groups of individuals with noticeably different characteristics

Question 22

Selection bias (threats to validity)

Answer 22

• Sampling procedure favours the selection of some individuals over others.
• If the sample doesn’t accurately represent the population, the results will not generalize to the population

Question 23

Manipulation (experimental)

Answer 23

Manipulate one variable to create two different treatment conditions.

• Third variable
• Directionality

Question 24

Measure (experimental)

Answer 24

Measure a second variable to obtain a set of scores in each treatment condition

Question 25

Comparison (experimental)

Answer 25

Compare the scores in treatment A with the scores in treatment B

Question 26

Control (experimental)

Answer 26

- The second distinguishing characteristic of an experiment is control of extraneous variables - Ensure observed relationship is not contaminated by the influence of other variables.

Question 27

Threats to validity (experimental)

Answer 27

- Assignment bias (different participants to different treatment groups with noticeably different characteristics)

Question 28

Mitigating threats to validity

Answer 28

Holding variables constant - making variables the same for every observation - environmental variables: standardize the environment and procedures - individual differences variables: hold demographic variables constant Matching - balance variables in each treatment condition Random assignment - passive control technique - disrupting systematic relation - unpredictable and unbiased procedure to distribute different values of each extraneous variable across the treatment conditions

Question 29

Manipulation check

Answer 29

- included in the study to measure whether the independent variable had the intended effect on the participant

Question 30

Placebo effect

Answer 30

Believed to be psychosomatic: the mind (psyche) has an effect on the body (somatic) - the individual thinking/believing it's effective, causes a response to the medication

Question 31

Placebo effect | Inactive drugs, Nonspecific therapy, Non alcoholic beverages

Answer 31

Believed to be psychosomatic: the mind (psyche) has an effect on the body (somatic) - the individual thinking/believing it's effective, causes a response to the medication

Question 32

What is a between subjects design?

Answer 32

- obtain each of the different groups of scores from a separate group of participants - comparing different groups of individuals - individual scores

Question 33

Advantages of subjects design?

Answer 33

- Each individual score is independent from the other scores | - Can be used for a wide variety of research questions

Question 34

Disadvantages of subjects design?

Answer 34

- Require a relatively large number of participants | - Individual differences

Question 35

Specific threats to validity (between subjects design)

Answer 35

- Differential attrition: when participants withdrawal from a study before it's completed - Communication: when participants from different conditions talk to each other... (Diffusion) - treatment effect spread between groups (Compensatory equalization) - untreated groups demand equal treatment (Compensatory rivalry) - untreated group works hard to show they can perform just as good (Resentful demoralization) - untreated group becomes less productive and motivated

Question 36

What does the t-statistic represent?

Answer 36

measures the size of the difference relative to the variation in your sample data