Unit 4

Question 1

What are the principles of the Selection of Participants?

Answer 1

Who are they?
How many are needed?
Where are they located?
How will they be selected?

Question 2

What are researchers in psychology usually interested in?

Answer 2

drawing conclusions about some very large group of people

Question 3

How do we call a very large group of people in research?

Answer 3

population
e.g.: American teenagers, children with autism, professional athletes, etc.

Question 4

What is usually studied in the population?

Answer 4

only a small subset or sample of the population

Question 5

What does representative mean in relation to the sample size?

Answer 5

sample is representative when it is a good reflection of a wider population and when the results derived from the experiment can be GENERALIZED to the population of interest

Question 6

What does Suitability mean in the selection of participants? What does it refer to?

Answer 6

inclusion and exclusion criteria including any restrictions based on demographic characteristics
-> refers to how well the chosen participants match the characteristics needed to answer the research questions

Question 7

What are demographic characteristics?

Answer 7

specific attributes of individuals that are often used to classify populations in research
-> include age, gender, race, ethnicity, occupation, marital status, geographic location

Question 8

What does the sample size determine?

Answer 8

the number of experimental units or subjects required, based on statistical methods and specify the procedure, usually randomized, to assign subjects to the experimental conditions

Question 9

What is a common critique of experiments in a study?

Answer 9

that a study did not have enough participants
-> difficult to generalize about population from a small sample

Question 10

What is a power analysis?

Answer 10

calculation when designing a study, that determines the number of participants you need to recruit to detect an effect of a specific size

Question 11

what is critical and essential to adequately design a study?

Answer 11

the sample size

Question 12

What is Hypothesis Testing?

Answer 12

H0 - Null hypothesis (no difference between study group)
H1 - Alternative hypothesis (There IS a difference between study groups)

Question 13

Which values are ideal for a good study?

Answer 13

a high power value
-> elevated chance of detecting a difference between groups (confirm the H1)

Question 14

What is Power value?

Answer 14

a percentage between 0 and 100%
-> it is a probability

Question 15

What increases when sample size increases?

Answer 15

power
-> when too low, low probability of rejecting the null hypothesis

Question 16

What is Power in sample size referred to?

Answer 16

Power is the probability of correctly rejecting the null hypothesis when the null hypothesis is false
-> power reflects the likelihood of detecting a true effect in the underlying population when such an effect exists

Question 17

What kind of value is excepted for a power value?

Answer 17

80%

Question 18

What does procedure refer to in the methods section of a research paper?

Answer 18

to the step-by-step description of how the study was conducted

Question 19

What does Accessibility Sampling Procedures refer to?

Answer 19

the methods and considerations involved in selecting participants for a research study
-> ensures that sample is appropriate for study goals

Question 20

Which 2 types of sampling are there?

Answer 20

1. Probability sampling
2. Non-probabililty sampling

Question 21

When does probability sampling occur?

Answer 21

when the researcher can specify the probability that each member of the population will be selected for the sample

Question 22

When does non-probability sampling occur?

Answer 22

when the researcher cannot specify these probabilities. Most psychological research involves non-probability sampling

Question 23

What is a common form of non-probability sampling?

Answer 23

Convenience sampling - studying individuals who happen to be nearby and willing to participate

Question 24

What does probability sampling require?

Answer 24

a sampling frame

Question 25

What is a sampling frame

Answer 25

it is a specific list, database or set of elements from which a sample is drawn for a research study
-> defines population of interest

Question 26

What is simple random sampling?

Answer 26

every member of the population has an equal chance of being selected for the sample

Question 27

What is a difficulty in random sampling in psychological research?

Answer 27

the populations are less clearly defined than the registered voters in a city

Question 28

What are Probability Samples?

Answer 28

Systematic random sampling