Higher Psychology RESEARCH REVISION

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1 Higher Psychology RESEARCH REVISION 1

2 The biggest change from the old Higher course (up to 2014) is the possibility of an analysis and evaluation question (8-10) marks asking you to comment on aspects of a research study. Key thing to remember is to focus on all aspects of it if it asks for method, results and conclusions, for example, you can expect the marks to be split three ways. To get full marks you must answer all parts of the question. 2

3 Experimental methods in Psychology You need to know about three types of experiment: laboratory, field, and quasi/natural. In any experiment, we need to have several things: Independent Variable= this is the difference between two conditions, set by the researcher Dependent Variable = this is the result of applying the independent variable Experimental or Alternative Hypothesis(H 1 ) = a statement of what you expect to find. This is what you are testing. Remember an alternative hypothesis is what you use for a non-experimental approach. Null Hypothesis (H 0 ) = a statement that no difference will be observed, or that the variables you are studying are not related One-tailed hypothesis = a statement about the direction of change, eg students will achieve better results when paid to sit an exam Two-tailed hypothesis = a statement that there will be change, eg students will achieve different results when paid to sit an exam. The direction of change could be up or down. 3

4 Ecological validity the extent to which your findings can be related to a real-life situation or applied to a different situation. For example, laboratory experiments have low ecological validity because they are artificial Demand characteristics where participants try to work out what the researcher is looking for. This may lead them to behave differently and reduce the validity of your research Extraneous Variable this is something which could interfere with your research. As far as possible, these need to be controlled. For example, people may behave differently depending on the time of day. Confounding Variable this is a type of extraneous variable which varies along with the dependent variable. This can therefore exaggerate results. THE EXPERIMENTAL METHOD Features of this are: It studies cause and effect by changing a variable (cause), we can see what difference this makes (effect) Makes use of independent and dependent variables Laboratory Experiments Take place under controlled conditions 4

5 Extraneous variables can be controlled or eliminated Can give standardised instructions and procedure, so that every participant has the same information Can select your participants Can be replicated (repeated) later. This makes it more likely to be reliable and valid. Shows the cause (IV) and effect (DV). Weaknesses of laboratory experiments are: It is artificial, so people may behave differently in a real life situation It does not have ecological validity Experimenter might be biased (they already know what they want to find out) and this can alter participants behaviour. 5

6 Type of experiment What is it? Why is it good? Weaknesses Laboratory Participants are taken out of their everyday activities and placed in an artificial environment where the researcher can control variables carefully. We can eliminate extraneous variables (ie something that might interfere with the result) Shows cause and effect Easy to replicate Low ecological validity we do not know if people would behave differently in real life Demand characteristics - people will try to figure out what the experimenter wants, and change their behaviour. This is sometimes called the Hawthorne Effect. Operationalisation the task itself may not reflect a real-life situation (eg trying to remember trigrams) Experimenter effect the nature of the researcher may bias the outcome 6

7 Type of experiment What is it? Why is it good? Weaknesses Field Participants are observed as they go about their everyday lives Greater ecological validity participants are behaving as they naturally would Can generalise from results, ie presume that you would expect to find similar results were it repeated Hard to control extraneous variables Can be expensive to arrange and hard to replicate Ethical problems, if participants do not know they are being observed 7

8 Type of experiment What is it? Why is it good? Weaknesses Natural Researcher makes use of a variable that they have no control over, eg changes in behaviour as a result of the smoking ban Can also be where ethical problems prevent random selection of participants. For example, if you want to test the effects on young people of alcohol abuse, it would be unethical to ask participants to begin drinking excessive amounts of alcohol. You would have to make use of data from people who are already binge drinkers. High ecological validity Low demand characteristics Eliminates sampling bias Lack of control over variables Ethics may include people who do not know they are being studied Impossible to allow for every possible extraneous variable 8

9 Survey Non-experimental methods Method What is it? Why is it good? Weaknesses A representative sample of Cheap and easy to participants are given implement questions to answer Can be questionnaire or interview Can use large number of people, so more representative Participants may not tell the truth Interviewer bias who is doing the research may affect the outcome Can use closed and open questions to gain quantitative and qualitative data Interview can be face-to-face or by telephone Questionnaire can be answered via an interview or in private Can be structured or unstructured Can take place anywhere, so avoid some problems of laboratories, eg participants feeling uncomfortable Standardised questions mean that every participant is asked precisely the same things Participants may misunderstand questions Demand characteristics participants may give answers they think they should 9

10 Method What is it? Why is it good? Weaknesses Naturalistic Observation Observing participants in their natural environment without attempting to interfere in any way. For example, observing factory workers using CCTV High ecological validity Subjectivity of researcher s observations Ethical issues if participants do not know they are being observed Participant Observation The researcher takes on a role in the group in order to observe. High ecological validity, but may be reduced by effect of researcher bias Subjectivity of researcher s observations Ethical issues if participants do not know they are being observed Observation schedule (used with either of the above) Allows researcher to code or analyse behaviour into categories Helps to make sense of qualitative data or wide range of quantitative data Participants may modify behaviour if they do know they are being observed Can lose some sense of qualitative data once transferred into code 10

11 Be able to describe the stages of the research process Choose topic Report findings Review literature Reach conclusions Form hypothesis Examine data Design study Collect data 11

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13 THE CASE STUDY METHOD The case study method Studies the story of a single case Often used for atypical/abnormal behaviour. For example, where a child has been neglected. This is because these cases are unusual Normally longitudinal, ie carried out over a long period of time It can have these features: Case history, eg someone s medical records Interviews; the individual(s) might be interviewed to discover information about their past or about present attitudes and feelings. Other people, such as relatives or friends or social workers and teachers, might be interviewed as well about the target case. Questionnaires can be used to assess attitudes and personality. Diaries kept by target individuals. Observation of the individual in relevant situations. Weaknesses of the case study method Bias people may not remember things correctly or want to give a certain impression of themselves Ethical problems because the cases are unusual, it may be difficult to keep them confidential May be difficult or impossible to apply your findings to any other case 13

14 TYPES OF SAMPLING We cannot use everyone in the world for any piece of research, so you have to find a group of people who are representative. That means, they are likely to be typical of the target population. So, if you want to find out what students in S5 (remember they have to be 16!) think about something, you try to select a group which is typical of people in S5. A good way of thinking about this is to think about possible extraneous variables, eg: Possible variable Boys and girls have different ideas Science students will have different ideas to RMPS students Different grades in S4 Representative sample Equal number of boys and girls Equal number of science students and RMPS students Equal numbers based on S4 results Random sampling every member of the target population (the people you want to study) has an equal chance of being chosen (eg picking names randomly from attendance registers). This is good because there should be no bias in who gets chosen. It is bad because the sample may not be representative, eg you may choose all the boys who don t like sport when you want to ask about attitudes to sport. Randomness can be achieved by assigning each potential participant a number, then using a random number generator to select. 14

15 Opportunity sampling you choose the participants who are available. For example, the S6 students in the common room on a Thursday afternoon. This is good because it is easy to arrange and you have control over whom you invite. Again, it may not be representative because all the laziest students are in the common room. Self-selection sampling - you get people to come to you. For example, you put a message on the plasma screens asking people to take part in a survey on SurveyMonkey. You do not approach them directly and you allow the participants to choose themselves. This may not be representative because only the attention-seekers volunteer! Systematic sampling very similar to random sampling, but you apply a system to it. You choose a random starting point, and after that there is a method for choosing (for example, every 10 th name after that). It has the same weakness as random sampling, in that it works best if you are working with a population which is quite similar. Quota sampling choosing a fixed number from groups within a population, for example 100 males and 100 females. Once you have your quota for each, you stop. This is easier than stratified sampling, but you could have a biased sample because all you are doing is filling your quotas. Stratified sampling the researcher divides the target population into strata (or groups), and then selects randomly within each stratum. This might be male/female, or age groups. It is different to quota sampling because each member of each group has an equal chance of being selected. This should lead to a less biased sample. 15

16 DESCRIPTIVE STATISTICS There are three types of average (measure of central tendency). Mean add up all of the data and divide by the number of numbers. This has the advantage of including every result. Median put all the numbers in order and choose the middle one. This has the advantage of reducing or eliminating the effect of extreme results which could skew the man. Mode choose the most common number. This would be used when you are looking to identify factors which are mutually exclusive (eg smokers and non-smokers). ETHICAL PRINCIPLES The British Psychological Society sets out what is ethical. Some principles are: Consent Participants should give fully informed consent. To be fully informed, they must be at least 16 and know what they are agreeing to Where possible, you should get consent BEFORE you start your research Right to withdraw Participants must know that they can withdraw at any time You must not put pressure on them to continue 16

17 Confidentiality When you publish your research, the participants should not be named or be capable of being identified You should not share individuals results with anyone apart from the researchers you are working with. Protection While people are taking part in your research, you are responsible for their safety The participants should not come to any physical or mental harm Deception You should be as honest as possible with your participants. If there is a need to lie during an research, you should inform the participants about it afterwards Debriefing After you are finished, participants should have the chance to talk about their experience. This provides qualitative data for you, as well as helping them come to terms with it. Giving advice Without professional training, you are not allowed to tell or imply to your participants that you can diagnose mental problems etc. 17

18 TYPES OF EXPERIMENTAL DESIGN Independent measures/groups different group of ppts for each condition of the IV Repeated measures same group of ppts for all conditions of IV Matched pairs type of independent measure, in which ppts in each condition are matched with each other. This should reduce any effect of participant bias. 18