Research methods

• Volunteer sampling- where ppts pick themselves through adverts, noticeboards or online
• Opportunity sampling- (convenience sampling) uses people who are available at the time the study is carried out and willing to take part
• Random sampling- everyone in target population has an equal chance of being selected. E.g., picking names out of a hat
• IV- the one the experimenter manipulates (changes). Has a direct effect on the DV
• DV- the thing being measured
• Operationalization of variables- making them measurable. E.g., cant measure 'happiness' but can measure how many times they smile within a certain amount of time
• Extraneous variables- variables that are in IV but could affect the result of the experiment. E.g., natural characteristics of a ppt
• Demand characteristics- a type of extraneous variable that occurs if the ppts work out the aims of the research study, they may being to behave a certain way.
• Experimental designs- independent, match pairs, repeated measures
• Independent measures- each ppt is selected for only one group. Randomization
• Matched pairs- each ppts is selected for only one group, but the ppts in the two groups are matched for some relevant factor (ability, age, sex)
• Repeated measures- each ppts appears in both groups so there are exactly the same ppts in each group
• Experimental- lab, field, natural
• Lab experiments- conducted in a well-controlled environment, not necessarily a lab, therefore accurate and objective measurements are possible
• Field experiments- conducted in everyday natural environment of the ppts. The experimenter manipulates the IV but in a real-life setting.
• Natural experiment- a naturally occurring IV is investigated that isn't deliberately manipulated, it exists anyway.
• Interview methods- structured- unstructured
• Structured interviews- formal. A fix predetermined set of questions is put to every ppts in the same order and in the same way
• Unstructured interviews- informal like casual conversations. The researcher deliberately adopts an informal approach to break down social barriers. No set questions
• Questionnaire methods- open questions, closed questions, postal questionnaires
• open questions- designed to encourage a full, meaningful answer
• Closed- "yes" or "no" or specific information. Limits the depth of the response
• Postal- the mail is delivered to the recipient's home or office