Lecture 2 Pyb100 PDF
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This lecture notes describes different research methods in psychology, such as naturalistic observation, case studies, surveys and experiments. It also discusses important concepts such as theories, hypotheses, and variables. The document also briefly discusses issues to consider when designing and conducting psychological studies.
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Dangers of misinformed practice - Bettelheim\'s theory of autism - Parents must be neglecting the children or mistreated for them to be autistic - Theory comes from his experience in a concentration camp and what he observed in behaviour from prisoner - he correlated...
Dangers of misinformed practice - Bettelheim\'s theory of autism - Parents must be neglecting the children or mistreated for them to be autistic - Theory comes from his experience in a concentration camp and what he observed in behaviour from prisoner - he correlated that with autistic behaviour - Frontal lobotomy - Synapses malfunctioning in frontal lobe causes severe depression, psychosis etc - Remove white matter in brain What are the problems with these approaches? - Bettelheim\'s theory of autism - Didn't use any factual evidence - opinion based - Didn\'t think about other variables that may impact the \"correlation\" - Posed himself as an expert and trusted his judgment -\> practice became harmful - Frontal lobotomy - Not based empirical data - Unethical - needed to warn people about the post-surgery effects - He wasn\'t an expert in psychology - Limitations of intuition and unsystematic observation What distinguishes science is the desire for evidence - Important to be critical Research concepts: theory and hypotheses - Good research is grounded in theory - Theory: a systematic ways of organising and explaining observations - Different schools of thought promote different theories - Leads to new predictions that can be tested - Based on available evidence - Broad - Good theories can - lead to more predictions and testable and backed by research - Fits the known facts - Is falsifiable -\> can be proven wrong - Theory provides the framework for a hypothesis - Hypothesis: a prediction about the relationship between two or more variables - Specific Example: - Being ignored by others on social media has a negative impact on state self-esteem - How could we test this? - Survey: - Must measure all variables - self esteem & social media - Experiment - 2 groups - group chat scenario where 1 group gets response and the other doesn\'t and evaluate feelings Doing research in psychology - Choosing a research design - Choosing a sample - Operationalising variables - Reliability and validity - Correlational and experimental research - Sources of bias - Ethics and integrity Different research designs are commentary A diagram of a diagram Description automatically generated with medium confidence Naturalistic observation - Researcher carefully observes behaviour without intervening - Participant observation - Researcher is also a participant - Advantages - In-depth observation of behaviour in natural setting, not contrived - Can provide new insights - Disadvantages - Reactivity: difficult to remain unobtrusive Case study - In depth investigation of an individual person/situation - Using interview, direct observation, records, psychological tests - Advantages - Can give starting point - Can provide rich, compelling data to support theory - Disadvantages - Representative of general population? - Subjectivity - investigators may see what they expect to see Surveys - Use questionnaires or interviews to gather information about specific aspects of behaviour - Advantages - Can get info that isn\'t observable (data on difficult-to-observe behaviour) - Accessible - data from a large sample - Disadvantage - Self report data can be unreliable - Intentional deception, social desirability, response sets, reliance on memory Correlational research - Looking for relationships among variables - E.g cyberostracism and self esteem - Useful for studying variables that the researcher can\'t manipulate - Personality, intelligence, age, sex - Can demonstrate that a relationship exists, but can\'t demonstrate [causality] Experimental research: establishing causes - To establish causation, the researcher - Manipulates one variable - Independent variable (IV) - Randomly assign participants to condition - Measures its effect on another variable - Dependent variable (DV) - Holding all other variables constant Population vs sample Population: - The *entire* group of people we are interested in studying Sample: - A *subset* of the population selected for study Random sampling: - Each member of the population is equally likely to be included in the sample - Least bias Representative sample: - Possesses the important characteristics of the population in the same proportions Convenience sample: - Recruit whoever you can; might not be representative - Most common in psych Operationalising variables: - Turning abstract concepts into concrete variables that we can measure or manipulate - In a correlational study, all variables are measured - How would you measure these variables? - Cyberostracism - Self-esteem - For an experiment, we need to manipulate the casual variable (the IV) and measure the outcome (the DV) - How could we manipulate cyberostracism? - How could we measure self-esteem? Reliability and validity - Reliability - Does the measure produce consistent results? Test-retest reliability - Does the test give similar values if the same participant takes it two or more times Internal consistency - Different items that measure the same variable should produce similar answers - be consistent Inter-rater reliability - Two testers who rate the same person on the same variable, should give similar ratings to the participant q - Validity - Does it measure what it\'s supposed to measure? - Is our measure related to other measures with demonstrated validity? - Is our measure related to an outcome it should be related to? - E.g., does high performance on an aptitude test predict performance on this job? Correlational research: Looking for relationships - Scatterplot - Plot one variable against another and look at the relationship - Correlational coefficient - Measures the direction and strength of the relationship between 2 variables - Can demonstrate that a relationship exists but can\'t demonstrate causality Experimental research: establishing causes - To establish causation, the researcher - Manipulates one variable - Independent variable (IV) - Randomly assign participants to condition - Measures its effect on another variable - Dependent variable (DV) - Holding all other variables constant Identify the variables e.g - Help is less likely in an emergency when there are several bystanders present. - Help DV, no. bystanders (IV) - Heart rate and blood pressure will be higher after viewing a violent film sequence as opposed to a nonviolent film sequence. - Heart rate and blood pressure (DV), film sequence (IV) - Heat stress leads to disorientation and confused thought. - Disorientation and confused though (DV), heat stress (IV) Basic elements of an experiment: - State your hypothesis - Manipulate the independent variable - Measure the dependent variable - Try to eliminate sources of bias/alternative explanations for results - Draw conclusions Holding other variables constant: - Experimental group - Exposed to the experimental condition of interest - Control group - Not exposed to the experimental condition, but otherwise treated identically to the experimental group - Random assignment - Participants are equally likely to be assigned to the experimental or control condition In a good condition, the only difference between the experimental and control groups is that the experimental group has been exposed to the independent variable Sources of bias: - Participant: - Demand characteristics - Participants respond in the way they think the experimenter wants them to respond - Placebo effects - Participants\' condition improves because they believe the procedures will help them - Experimenter: - Expectancy effects - The experimenter\'s expectations and behaviour bring about change rather than the IV itself - To eliminate bias: - Single-blind study - Participant is unaware of the purpose of the study/which condition they are in - Double-blind study - Both experimenter and participant are unaware of purpose of the study/condition - Confounding variables: - Another variable that could be producing the observed effect - Confounding occurs when something other than your IV varies systematically across conditions and is correlated with the DV - E.g. if the experimental group walked a dog and the control group sat quietly - IV = time with dog, DV = happiness, confound = activity level - Affects the internal validity of a study - Sampling bias: - Sample is not representative of the population as a whole - Affects the generalisability of the results