research methods lec 2

Question 1

define

correlation

Answer 1

occurs with or after

A in variable a occur with or after A in variable b.

Question 2

define

causation

Answer 2

A variable a results in A variable b

change in variable A must occur is necessary for change in variable B

Question 3

3 goals of scientific approach

Answer 3

description (qualitative)
prediction (correlational)
understanding-controlling (experimental)

Question 4

psychology uses a ____ approach

Answer 4

scientific

Question 5

scientific approach using ____ _____

Answer 5

empirical
experimental methologies
to understand phenomena of interest

Question 6

define

non-experimental research

Answer 6

observational

cannot demonstrate causation

Question 7

define

experimental research

Answer 7

can demonstrate causation due to its key features
manipulation
control of extraneous variables

Question 8

define

IV

Answer 8

Independent variable= manipulated by experimenter

Question 9

define

DV

Answer 9

Dependent variable

= participants response

Question 10

in terms of variables, what do experiments ask

experiments investigate the effect of ____ on ___

Answer 10

whether systematic variation in one variable produces variation in another variable

IV on DV

Question 11

define

observation

Answer 11

the quality/intensity/direction of the DV

Question 12

define manipulation

Answer 12

the quality/intensity/direction of the IV change is controlled by the experimenter

Question 13

change of _V => change in _V

this allows us to test the effect instead of waiting for it to

Answer 13

IV
DV

occur naturally

Question 14

If Iv changed and DV is changed as a result then there is ______ about the ____ relationship

Answer 14

strong evidence

causal relationship cause DV occurs because/after IV

Question 15

experimental group gets _V

control group get _V

Answer 15

experimental treatment = IV

control group = no treatment = no IV

Question 16

RCT aka

Answer 16

randomised control trial

Question 17

3rd variable aka

Answer 17

confounding variable

causes changes in the variable that is being measured

Question 18

extraneous

Answer 18

unrelated

Question 19

method to control extraneous variables (1)

Answer 19

1 = ensure all important factors are the same in both experimental and control group

Question 20

validity _ types =

Answer 20

2 types
internal validity (iv)
external validity (ev)

Question 21

define

internal validity

Answer 21

outcomes - consequences of the relationship between the IV and DV

no alternate explanations = therefore all extraneous variables are controlled for

therefore with confidence = change in IV = change in DV

Question 22

define

external validity

Answer 22

• extent to which the results can be generalized
  to the pop from the sample
  OR
  to the real world from experimental setting

IV => DV

relo outside experimental situation???

Question 23

trade-off situation between ___ and ___

Answer 23

internal and external validity

Question 24

^ iv =

Answer 24

high internal validity = more experimental control required = risk of compromising the ev

ev = results valid in the real world

Question 25

effect of ___ on ___ occured by chance = explained by the ___ behind ____ ___

Answer 25

iv on ev
reasoning
inferential statistics

Question 26

reasoning behind inferential statistics 3

Answer 26

3

1 assume there was no effect (Null hypothesis H.) groups aren’t diff

2 find the prob. of getting the result we got, given that the Null hypothesis H. is true

3 if the result is

pretty likely to have occurred by chance, then there is no reason to believe that there was an effect.

pretty unlikely to have occured by chance, then we are prepared to believe that there was an effect.

Question 27

define

probability of an event

Answer 27

is the ratio of the no. of observations of that event over the no. of all observations of that event

Question 28

define

Null Hypothesis H.

Answer 28

we don’t believe that there is an effect because many events may occur just by chance

Question 29

hypothesis testing we assume that

Answer 29

estimate the probability of our result to have occurred by chance, assuming the Null hypothesis is true.

Question 30

if probability of an event occuring =very low ___ %

Answer 30

less than 5.% = ready to believe that there is real effect and we reject the null Hypothesis

( we never accept Null hypothesis)

Question 31

snd aka

Answer 31

signal detection theory

Question 32

define hypothesis testing =

Answer 32

1
decisions are based on uncertain information. 4 possibilities = each expressed as a conditional probability

the probability of type 1 occurring is in fact controlled by the researcher

mainly interested in minimising the type 1 error
p-value indicates the probability of a type 1 error

there is no 100% certainty with statistics

Question 33

alpha-level of hypothesis testing =

Answer 33

the alpha level represents the probabilty of a type 1 error = aka = level of significance

Question 34

the accepted level in psychology =

medical sciences =

Answer 34

psychology = 5% alpha 0.05

medical sciences = 1% alpha 0.01

Question 35

a level of significance of alpha 0.05 represents =

Answer 35

the researcher is willing to accept a 5% chance of making a type 1 error

Question 36

when 2 pop.s are different the sample means =

Answer 36

tend to be larger for the larger pop ( pop with highest values)

Question 37

define

t-distribution =

Answer 37

in small-medium samples the differences in sample means are described by the

t-dist symmetrical about zero
has bell-shaped curve

Question 38

distribution of mean differences

Answer 38

assuming the two populations are the same ( H0)

therefore, can use the normal dist to find the probability of finding the differences between the sample means = if so = suggest that there is difference between the 2 pop.s

Question 39

reasoning behind hypothesis testing =

Answer 39

extremes of normal dist = 2.5 each = total 5% of extreme values

region = region of rejection

Question 40

if mean difference falls within the ___ region then __

since

Answer 40

region of rejection

we can reject H0

at alpha = 0.05
z > 1.966 or -1.96

Question 41

t-test =

Answer 41

involves using a formula that returns a t-statistic = often called = t-obtained

Question 42

t-obtained =

Answer 42

the t-statistic derived from the t-test

= difference in means / variability

Question 43

non-experimental research pros=

Answer 43

good as pilot study = to inform where possible causal relationships could be

complex = real-world issues aren’t easily studied in lab

in many situations IV = can’t be manipulated

sometimes - unethical

need to design study groups that already exist via quasi-experimental designs

Question 44

descriptive research =

Answer 44

seeks to describe phenomena rather than to manipulate variables

Question 45

methods of descriptive research =

Answer 45

case studies
naturalistic observation
survey research

Question 46

define

case studies

Answer 46

in-depth study of the behavior of 1 person in a small group

Question 47

case studies = information=

Answer 47

used in clinical research (.e.g Freud)

used when large numbers of participants aren’t available

cons
small sample size
susceptibility to researcher bias
problem of a rare case

Question 48

define

naturalistic observation

Answer 48

in-depth study of the phenomena in its natural setting

Question 49

pros and cons of naturalistic observation=

Answer 49

pros
good generalisability

cons
observation per se can alter behavior

can’t establish cause of behaviour

Question 50

define

survey research =

Answer 50

asks questions of large numbers of persons to gain information on attitudes and behaviours

2 approaches

Question 51

approaches of survey research =

Answer 51

2

questionnaires
interviews

Question 52

cons of survey research=

Answer 52

sampling issues

people may not respond accurately