research methods Flashcards
define alternative hypothesis.
a prediction that states what the effect of the IV will be on the dependent variable investigation
define null hypothesis.
a statement that predicts there will be no effect of the IV on the DV
what are the 2 types of alternative hypothesis and define them.
- directional-difference predicted or relationship and the direction of the effect
- non-directional-difference predicted or relationship but no direction specified
writing frame for directional hypothesis.
there will be higher number of/more…who/when…than…who/when….
writing frame for non-directional hypothesis.
there will be a difference in the…between…and…
what is the operational definition?
giving clear definitions of what these variables are and exactly how we are going to measure them e.g. a score out of 20
what are the 7 extraneous or confounding variables?
- situational variables
- participant variables
- investigator effects
- social desirability
- the Hawthorne effect
- demand characteristics
- order effects
define situational variables.
outside influences on the experiment e.g. time of day,weather,noise,type of room
define participant variables.
individual differences between participants e.g. IQ, age,gender,social class,fitness etc
define investigator effects.
any conscious or subconscious bias caused by the investigator e.g. giving ratings based on opinion
define social desirability.
when participants change their behaviours or answers to conform to social norms
define the Hawthorne effect.
when participants change their behaviour when they know they are being observed
define demand characteristics.
when participants pick up cues from the situation during an experiment, try to guess the aim and modify their behaviour
define order effects.
effects that occur in a repeated measures design, participants behaviour is affected by the order they experience the conditions
what are the 4 controls for extraneous or confounding variables?
- randomisation
- standardisation
- random allocation
- counterbalancing
define randomisation
the use of chance in order to control the effects of bias when designing materials and deciding the order of conditions
define standardisation
using the exact same formalised procedure in a research study
define random allocation
an attempt to control for PARTICIPANT VARIABLES in an independent group design, ensures each participant has the same chance as being in one conditions any other
define counterbalancing
an attempt to control for ORDER EFFECTS in a repeated measures design :half participants in one order and the other half in the opposite order
what is repeated measures?(CV)
all the participants do all conditions
what is independent groups?(CV)
half of the participants do one condition and the other half do another
what is matched pairs?(CV)
participants are pretested for a characteristic and matches with someone with similar characteristic
what are single and double blind trials?
(single) the participant doesn’t know what group they belong to
(double) the participant and experimenter doesn’t know what group they belong to
what does deceiving help control?
social desirability
what is a lab experiment?
taken place in controlled setting
researcher manipulates IV and measures DV
what is a field experiment?
takes place in a natural setting e.g. town centre
researcher manipulates IV and measures DV
what is a natural experiment?
natural environment
IV has not been manipulated
what is a quasi experiment?
investigation where two groups are compared based off a characteristic about them.
what is the difference between natural and quasi experiment?
in quasi IV selected by the researcher whereas natural IV occurs naturally
strengths and weaknesses of lab experiments.
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STRENGTHS🙂
-easy replication-standardised-increases reliability
-
WEAKNESSES😠
-tasks often lack mundane realism(real world activities)
-high chance of demand characteristics due to ppts knowing they’re being tested
strengths and weaknesses of field experiments.
STRENGTHS🙂
-high ecological validity(people behave more natural)
-reduced demand characteristics
WEAKNESSES😠
-lack of control of extraneous variables e.g. situational
-impractical-time consuming and expensive
-ethical issues(consent)
strengths and weaknesses of natural experiments.
STRENGTHS🙂 -excellent research opportunities -reduced demand characteristics WEAKNESSES😠 -random allocation not possible -small sample size-generalisation of results can be difficult
strengths and weaknesses of quasi experiments.
STRENGTHS🙂
-can be tested under controlled conditions
WEAKNESSES😠
often artificial-results may be low in ecological validity
what is systematic sampling?
target population is listed and ordered and every nth person is selected to be in sample
what is stratified sampling?
population chosen by age, gender, ethnicity e.g
what are all the types of sampling?
- random
- systematic
- stratified
- opportunist
- volunteer
pros and cons of random sampling?
pros-individuals all have equal chance of being selected
-eliminates sampling/researcher bias
cons-requires a lot of time to conduct
pros and cons of systematic sampling?
pros-avoid researcher bias
cons-hard to achieve due to costs and time taken to select a set of participants
pros and cons of stratified sampling?
pros-
cons-determining and constructing accurate strata would consume a large amount of time and be difficult to do
pros and cons of opportunity sampling?
pros-convenient
cons-lack of care about ppt variables causes representation of population to decrease heavily
pros and cons of volunteer sampling?
pros-less time consuming
cons- has great volunteer bias.
