Research Methods Flashcards
Advantage of Naturalistic Observations.
High Ecological validity.
Disadvantages:
- poor control of extraneous variables so can lead to reduced internal validity.
- observe bias - only wrote down what they think in necessary (also can reduce internal validity) this can be reduced by using more than one observer.
- no IV
- Observing something in a natural environment.
- inter-observer reliability - More than one observer compare using correlation.
There can also be:
Participant and non-participant observation.
Unstructured Observations.
No system - record all relevant behaviour
- Too much to record
- Behaviours recorded will be the most visible; may not be the most important
Structured Observation.
Observers have to avoid being overloaded so focus on:
1) Event sampling
2) Time sampling
To avoid making immediate judgements observers now tend to use videos to record data.
Controlled Observations.
- There is some experimenter control.
- The participants know they are being observed which may affect results.
- Ainsworth and Bell’s strange situation is an example of a controlled observational study.
Observations.
- when conducting an observation you must categorise the specific behaviours you aim to observe.
- so if you are studying aggression you would categorise the behaviours by stating that aggression would be measured by hits or kick etc OR you could RATE the behaviour by counting the kicks and hits.
- controlled observations are very much like experiments but more detailed info can be obtained.
BUT - artificial conditions can influence behaviour and there are the problems of investigator effects and means characteristics.
Naturalistic Observation.
- behaviour is studied in a naturalistic setting - no interference from investigator.
Controlled Observation - behaviour is studied under controlled conditions.
Observations.
- Participants are observed engaging in the behaviours being studied and the observations are recorded.
Weakness of Natural Experiments.
Lack of randomisation so the sample may not be able to be generalise to the wider population. Also there are ethical concerns which include taking advantage of people.
Advantages of Natural Experiments:
1) Participants are unaware that they are taking part in an experiment so behaviour tends to be realistic - making findings more reliable.
2) PERMITS the study of variables that it would be unethical to manipulate.
Natural Experiments.
- Makes use of a naturally occurring event. THE INDEPENDENT VARIABLE CHANGES NATURALLY - no MANIPULATION.
- In St Helena people didn’t receive TV until 1995 so psychologists were able to compare children’s level of aggression before the introduction of TVs their aggression afterwards.
- IV occurs naturally and can’t be manipulated.
Field Experiments.
- Take place in natural settings but the experimenter still manipulates the IV. Higher in ECOLOGICAL VALIDITY.
- But low in INTERNAL VALIDITY because it is hard to control extraneous variables which may affect the outcome and also participants may guess that they are taking part in an experiment and of this happens their behaviour wouldn’t reflect how they would normally act.
- Higher in ecological validity - external validity.
Weaknesses of LAB experiments.
1) Artificial - so they lacking ecological validity. This means that the findings may not reflect what would happen in real life situations.
2) Demand Characteristics may lower validity - people may use clues in the environment to guess what is expected of the, and then would act accordingly.
3) Ethical Issues - In LAB experiments people may feel as if it is difficult to withdraw and discontinue their participation as it is often a more pressured environment.
Strengths of LAB Experiments.
- High levels of control means that experiments are high in internal validity. It is easy to see that the IV is having an affect on the DV.
- High levels of control also means that it is easy to repeat the experiment I’m exactly the same way to assess the reliability of the study (high reliability if we get the same result)
- Internal Validity - control, are we testing what we set out to test,
- External - generalise our findings out of the research setting.
- Ecological Validity - can we generalise findings to other places/settings.
- Mundane Realism - reflex the real world.
- Inter-rater reliability.
Volunteer sample.
Relying solely on volunteers to make up the sample.
Advantage:
- Access to a variety of participants - more representative less biased.
Disadvantages:
- The sample is biased Volunteer Bias, as participants may be more motivated and/or have more time on their hands.
Opportunity Sample.
Selecting people who are most easily available at the time of study.
Advantages:
- Easiest method as you use the first participants you find - less time consuming than the other sampling techniques.
Disadvantages:
- Biased as the sample comes from only a small part of the target population.
Random Sampling.
- Using a random technique so that every member of the target population has an equal chance of being selected.
Advantages:
- All members of the target population have an equal chance of being selected - so this technique is unbiased.
Disadvantages:
- Does not guarantee a representative sample (area bias and so on) so can be biased.
How to get a sample.
Random Sampling:
- selecting participants completely at random - the best method - computer generated.
Opportunity Sampling:
- using people who are readily available.
Volunteer Sampling:
- asking people to help you by taking part in your study - usually through advertising.
Selection of Participants and Sampling Techniques.
When conducting our research we often want results to generalise to the wider population so we need a REPRESENTATIVE sample.
- Some studies have only used students so there is sampling bias.
- Volunteer, opportunity, random sample and demand characteristics.
To overcome order effects counterbalancing should be employed.
AB/BA A=Alcohol/B=No-alcohol
Half the participants do condition B first then condition A.
AB = artificially High/Low
BA = artificially High/Low
Matched Pairs Design.
Advantages:
- Controls some participant variable which reduces the effects of individual differences.
Disadvantages:
- It is very difficult to control/match all variables because you rarely find two individuals who are exactly the same.
Repeated Measures Design.
Advantage:
- Controls ALL individual differences and requires fewer participants.
Disadvantages:
- There can be order effects which would lower the internal validity.
Independent Groups Design.
Advantages:
- No order effects, no loss of participants as they are split into different groups.
Disadvantages:
- Individual differences (like natural ability) may affect results.
Experimental Design. (Different from research methods).
Experimental design if an experiment has TWO conditions (parts)
- Independent Groups Design - different participants in each group - randomly assigned.
- Matched Pairs Design - Different participants in each condition but they are matched according to age/sex etc -‘to try and make the test fair.
- Repeated Measures Design - Participants do both conditions.
Operationalisation of Variables Including independent and dependent variables.
- Before we can measure the value of a variable it must first be operationalised.
- This means it must be defined in terms of something that can be measured.
- Making your variables so specific that another researcher could copy you I’m exactly the same way.
- We must Operationalise the Independent variable so the other researchers can see how we have measured it. Be specific.
- So if we are testing the effect of the time of day we revise on learning we would.
- Operationalise the IV by stating that the IV is whether the participants learn at ten in the morning or ten in the evening.
- If we are testing whether students who revise have better exam results we would.
- Operationalise the IV by stating we would use students who revise for 4 hours a week versus those who don’t revise.
Two Conditions.
If an experiment has two conditions, the ‘normal’ condition is called the control condition and the other is called the experimental condition.
So, if we are testing if caffeine increases concentration, the control contrition would be the condition without caffeine.
Other Variables.
Experiments can sometimes include other variables that are ‘extra’ and can be hard to control. These may also affect the outcome (the DV).
These are called extraneous variables light, noise, temperature, differences in age/ability etc.
To ensure high validity, extraneous variables HAVE to be constant for ALL participants OR have to be eliminated.
Variables.
- Independent Variable, the variable that the experimenter manipulates. Assumed to affect the DV.
- Dependent Variable. The variable that you think will be affected by the IV (DV is dependent on the IV) The variable that is measured.
- Participants remember more words before lunch then after lunch.
Variables.
- In an experiment the relationship between two things is investigated. E.g. We may study the relationship between revision and exam success.
- These two things are collectively known as variable.
Experimental/Alternative hypothesis. The
- Experimental/Alternative hypothesis may be one tailed (directional) or two tailed (non-directional).
- A directional hypothesis will predict the effect of the IV on the DV
- A non directional hypothesis will state that there will be an effect but won’t state the direction.
What is the Null Hypothesis?
This simply states that the independent variable will not affect the dependent variable. You will have to believe that the null hypothesis is true until you have finished your research and you analyse your findings.
E.g. Loud noise will not affect a persons ability to remember information read in a textbook.
- Null is true until you prove yours is Null = statement of no effect.
What is an Experimental Hypothesis?
- A clear guess. A precise, testable statement.
E.g. If I am studying whether noise affects a persons ability to study, my hypothesis might be that - loud noise will affect a persons ability to remember information read in a text book.
-We use hypotheses with ALL research methods. With anything other than an experiment the experimental hypothesis is called the Alternative Hypothesis.
