What are the 4 sampling methods (gathering people to take part in a study )and definition of them
Self selecting = when the person volunteers to take part (known as a volunteer sample ) example = putting an advert in a newspaper or on a notice board
Opportunity= when people who are available at a given time and place are selected by the researcher for the study
Random = each member of the target population has an equal chance of being selected (e.g names could be pulled out of a hat)
Snowball= when participants are asked to contact their friends and family to ask them to take part in the research, they in turn then ask other people
Advantages and disadvantages of self selecting sampling
A= likely to turn up and cooperate , choice of participant is not biased by the researcher, participants are usually aware of the purpose of the research (so consented to take part)
D= people who take part in research may not be representative of the population as a whole (may be more cooperative ) and biased based on where you advertise , smaller sample size, possible time and cost of advertising
Advantages and disadvantages of opportunity sample
A= quick and easy to obtain as you are selecting who is there at the time , larger sample size
D= often unrepresentative as the people available to the researcher may not be typical of the population as a whole, less ethical as participants may feel obliged to take part and continue
What is a laboratory experiment
the IV is manipulated by the researcher and the experiment is carried out in a laboratory or other contrived setting away from the participants normal environment
Advantages and disadvantages of a lab experiment
A:
-high level of control produces scientific research which is easy to replicate
-we can be sure that the variable we manipulated (the IV) is the factor affecting the dependant variable
D:
-low ecological validity due to artificial settings
-the artificial setting or tasks do not reflect real life events, so behaviour may be artificial (can cause demand characteristics)
Two types of data (Q and Q) which can be collected and what is it
Quantitative = when data is in number format
Qualitative = when data is in written format
Advantages and disadvantages of quantitative data
A= easier to analyze, compare and see patterns in data, easier to summaries and present in tables and graphs, can check reliability of results
D= less ‘rich’ detailed information than qualitative (lack of depth and detail), less insight into the reasons for behaviors shown
Advantages and disadvantages of qualitative data
A= often ‘richer’ more detail and depth, more insight into the reasons for the results obtained
D= difficult to analyse, compare and see patterns in it, cannot display easily in graphs/descriptive statistics, more subjective so open to researcher bias
what is a field experiment
the IV is manipulated by the researcher but this time the experiment is carried out in the participants normal surroundings
what is a quasi (or natural) experiment
the IV is naturally occurring (e.g cloudy conditions versus sunny conditions, morning versus afternoon), not manipulated by the researcher
advantages and disadvantages of a field experiment
a:
-a more realistic setting for a study so higher ecological validity
-behaviour is more likely to be a more truthful reflection of real life action (avoids demand characteristics)
d:
-lack of control of the setting means we cant always assume the IV is influencing the DV = risk of extraneous variables influencing behaviour
-there may be ethical issues as participants might not be aware they were in an experiment (informed consent )
advantages and disadvantages of a quasi experiment
a:
-can study the effect of factors the researcher cant manipulate such as the weather (sun or rain)
-usually high level of ecological validity due to the naturally occurring IV
d:
-they can be very difficult to replicate due to the naturally occurring IV
-lack of control over all the variables e.g the social setting, lifestyles= these may be confounding variables that affect the results
what are the three experimental designs and define them
-independent measures design =This involves having different participants in each condition
-repeated measures design = Involves the same participants taking part in all conditions
-matched participant design = this involves using different people in each condition but an attempt is made to make the participants as similar as possible on certain key characteristics (any that might influence the findings). This is done by testing the individuals on the key characteristics, pairing them based on similar scores and then placing one member of each pair into each group
advantages and disadvantages of repeated measures design
A:
-participant variables will not affect results as it is the same people (with the same range of abilities) who take part in each condition of the experiment
-Half the number of participants are needed to get the same amount of results as in other designs
D:
-Order effects (either getting worse due to fatigue or getting better due to practice) can affect the results from the second condition
-To avoid order effects, it may be necessary to create additional test materials (for use in the second condition) that are yet of an identical difficulty – this may be very hard to achieve.
advantages and disadvantages of independent measures design
A:
-There is no risk of results being affected by the order in which participants do the task because they only do the task once (order effects wont occur )
-It is possible to use the same task in each condition, controlling for any differences in this as a possible extraneous variable and making it easier for the researcher.
D:
-Results can be affected by participant variables because there are different people in each condition and, inevitably, there will be individual differences between them
-Twice as many participants are needed as in repeated measures design just to get the same number of results.
advantages and disadvantages of matched participant design
A:
-You get the benefits of both the other designs: order effects are avoided as participants only take part in one condition of the experiment AND participant variables are not a problem as participants are matched on relevant characteristics.
D:
-More complicated as participants need to be pre-tested on a relevant characteristic so that they can then be distributed evenly across the different conditions
-Twice as many participants are needed as in repeated measures design just to get the same number of results.
what are the 3 types of extraneous variables and what they are
-participant variables = characteristics of participant that might affect performance on task
-situational variables = factors related to the task itself or the environment in which it is completed might impact how participants perform
-researcher effects =where the researcher either influences the behaviour of the participants; or their prior expectations impact on how they analyse the results of a study or who they select as participants
how can the types of extraneous variables be controlled for
-participant variables= either have same people in each condition (repeated measures design) or extremely similar people (matched participant design, if independent design used make a point of allocating participants to conditions on a random basis
-situational variables =having different people in each condition will avoid problem (use matched participants design or independent design), if a repeated measures used then this should be counter balanced (participants split into 2 groups and group 1 does condition A then B but group 2 does condition B then A )
-environmental factors = impose controls on the experiment to ensure that there are as few differences as possible between 2 conditions e.g time of day, temp, noise
-demand characteristics= don’t tell participant the aim of the investigation
what is single blind and double blind research and why may a researcher do it
single blind= when the participants do not know the aim of the study (i.e they are blind to the aim of the research)
double blind = when neither the participants nor the people carrying out the research know the aim of it
-double blind can reduce the risk of researcher effects (when results are affected by the researchers behavior) and can also eliminate the dangers of researcher bias (when a researcher allows their hopes and expectations for what the data will look like to affect the data they choose to hold onto or reject from a study)
what is an alternative and null hypothesis
-alternative= this predicts how one variable (the IV) is likely to affect another variable (the DV), it predicts that the IV WILL affect the DV e.g people will complete a jigsaw significantly faster after drinking a cup of caffeinated coffee than after drinking a cup of decaffeinated coffee
-null= this predicts that the IV will not affect the DV, it predicts that any difference seen will be due to chance factors rather than the independent variable e.g there will be no significant difference in the time taken to complete a jigsaw in the morning than in the evening
what is a two tailed and one tailed hypothesis
-two tailed = this predicts that the IV will have a significant effect on the DV but it does not predict the direction this effect will go in e.g rainy weather has a significant effect on peoples levels of happiness
-one tailed=this predicts that not only that the IV will have a significant effect on the DV but also the direction this effect will go in e.g men who have beards are perceived as significantly older than clean shaven men
what is operationalising
-refers to the process of making variables physically measurable or testable
-e.g measuring whether a person is healthy or unhealthy could be healthy= eats more than 5 fruit or veg a day, unhealthy= eats less than 5 fruit or veg a day
advantages and disadvantages of random sampling
A:
-More representative (of the target population) as everyone has an equal chance of being selected
-eliminates researcher bias as the researcher has no control over who is selected to be in the sample
D:
-Difficult to get all the names of everyone in the target population
-They may not be willing to take part (so could still become biased)
-can be time-consuming and impractical
advantages and disadvantages of snowball sampling
A:
-Fairly easy to recruit a large sample as you only need to recruit a few participants and they recruit the rest
D:
-May be more likely to get friends of participants so they could have similar characteristics
-May not get enough participants if they don’t recruit others
-There is no way of knowing whether the sample is representative of the population
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Unit 1- experiments30
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Core Studies Social Area - Milgram14
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Core Studies Social Area- Piliavin17
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Core Studies Developmental Area- Bandura16
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Psychological Perspectives13
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The Debates Pack27
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Unit 1- Methodological Issues7
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Core Studies Developmental Area- Kohlberg13
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Core studies cognitive area- moray29
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Core studies cognitive area- Loftus and Palmer22
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Unit 1- Self Report pack19
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Core studies individual differences area- Freud22
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Core studies individual differences area - Gould26
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Unit 1 - Correlation14
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Core studies Biological area- Sperry15
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Contemporary core studies Developmental area- Chaney et al16
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Core studies Biological area- Blakemore and cooper21
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Contemporary Core studies Developmental area- Lee et al20
