Methods

Methods 1

  1. Intuition - when you believe you know something because it feels so 

  2. Pure Observation - take your own senses to observe the world in a particular way

  3. Authority - world works in a particular way because an expert says so 



Problem with “pure” observation 

  1. Can’t be perceived/ not possible 

  2. Not always true/ misperception 

    1. Ex. Visual illusions 

  3. Own observation can change overtime 

  4. People disagree on what they are experiencing 



TERMS 


Science 

  • Community of people following agreed rules and policies for observing, predicting, and explaining some part of our world 


Scientific method creates:

 

 Theories 

  • Possible explanations for why or how something works 


Hypothesis 

  • Predictions about what should happen in a specific situation 


Studies / experiments 

  • Observational tests of a hypothesis by creating or finding situations in which the hypothesis should hold true 


Universality 

  • When formulating a hypothesis or theory, the number of people we believe it applies to 


Science: assumptions 

  1. Human nature can be studied through scientific testing 

  2. Some parts of human are fixed, predicable, and universal 

  3. Generalization are made about people as a group, not about specific individuals 


Science is not the only way of knowing things, just primary method used in psychology 


Scientific observation 


Scientific skepticism 

  • Should not be attached to a specific theory or hypothesis 

Peer review

  • Send your conclusions for review from other scientists 

Replication 

  • Multiple studies done the same way should generate similar data

Falsifiable Hypothesis 

  • Make inflexible predictions that can be shown to be false with observation 



Scientific observation 


To deal with impossibility of observation we develop new tools 

To deal with unreliability of observation

  • Openness: all data should be publicly available  

  • Double-Blind experiments: neither participant nor person collecting the data should be aware of what the hypothesis is



Scientific process 


FULL CIRCLE (definitions are below)

Hypothesis → Operationalize → Measure → Analyze and Interpret → Report 


Operational Definition

  • A description of a psychological property in measurable observable terms 

  •  Ex. stage fright 

    • Measure heart rate (good one)

    • # of times person say “im so nervous” (not the best)


Measure 

  • Instrument: anything that measures the operational definition 

    • Heart rate monitor: 

      • Measure beats per min

      • How hard the heart is beating 

  • Construct validity: measure what it's supposed to measure 

  • Reliability: it gives similar measurements each time it is used 

  • Power/ Sensitivity: detect small differences in the measure (fine grains of differences)

  • Ex. 

    • Questionnaires, computer tasks, physiological measures 


Definition + instruments = data - a collection of measurements 

Methods 2 

Study Design/ Methods: used in psychology to observe and interpret data


  • Naturalistic Observation =: collecting data in the real world by simply observing in a natural environment 

    • Ex. looking at child development at a school


  • Case-Studies = collecting data on one or few unique individuals 

    • Ex. individuals who have brain damage 


  • Correlational Studies = estimated numerical prediction between 2 measured variables 

    • Ex. study of age and political party 

      • Estimate what age affiliates with a certain political party 

    • Types of correlation and ex

      • Positive correlation (more sleep associated with more stress)

      • No correlation (more sleep has no association with stress)

      • Negative correlation (more sleep associated with less stress)

    •  Problem: 

      • Directionality problem: correlation of A might cause B or B might cause A

      • Third Variable Problem: third, unmeasured variable C (confound)

      • Coincidence: some things drawn together through luck and random 

  • Spurious correlation: strongly correlated variables that we know are not casually related, and correlate because of confounds or coincidence 


 

  • Experiments: one variable is manipulated by an experimenter to see its casual effect on another 

    • Experimental group: do the task that is “abnormal” (ex. Deny sleep)

    • Control group: do the task that is “normal” (ex. Sleep normally)


  • Independent variable (IV): the variable manipulated and predicted to have a casual effect


  • Dependent variable (DV): the variable mature, and predicted by to caused by the IV


  • Random selection/ sampling participants should be chosen from the study randomly from the whole general population


  • Random assignment: participants are put into the IV groups randomly 


  • Solution to directionality: you control the direction by choosing which variable you manipulate and which you measure 


  • Solution to third-variable(s): two groups will be theoretically identical in every third variable, so only difference will be from the manipulation you made 


  • Solution to coincidence: studies are replicated by other researchers multiple times to make sure the result wasn’t by chance 



2.1 Empiricism: How to know stuff 


Empiricism -accurate knowledge of the world can be acquired by observation 



Scientific method -procedure for using imperial evidence to establish facts 

  • Also tells us the truth about the world is to:

    • 1) develop a theory 

    • 2) derive a falsifiable hypothesis 

    • 3) test that hypothesis by observing the world 


Theories -explanations of natural phenomena (idea about how something works)


Hypothesis -falsifiable prediction made by a theory 


Falsifiable -using the scientific method to evaluate its accuracy 




Empirical method -set of rules and techniques for observation 

  • Why: because human eyes may see inaccurately 


Method -technologies that enhance the powers of the senses 


Human beings have three qualities that make them more difficult to study:

  • Complex (human body is complex with 100 billion interconnected neurons)

  • Variable (no one feels exactly the same thing under exactly same circumstances)

  • Reactive (people tend to think, feel, act different when observed or not 



Methods of observation -allow them to discover what people do 


Methods of explanation -allow them to discover why people do it 












2.2 Methods of Observation: Discovering What People Do 


Measurement (two steps)


1) Operational definition -description of a property in measurable terms 

  • Ex. define happiness as “the amount of dopamine in a person’s brain” or “amount of smiles in an hour”


In an operational definition, one key feature is: 

  • Construct validity = specified operation are generally considered good indicators of the specified properties 


  • Ex. using smiles to define happiness would seem logical but not eating no. of chocolates 


2) In a good detector, two key features are: 

  • Power = detector’s ability to detect the presence of differences or changes in the magnitude of a property 


  • Reliability = detector’s ability to detect the absence of differences or changes in the magnitude of a property




Demand characteristics -aspects of observational setting causing people to behave as they think someone else wants or expects 

  • Ex. friend ask you if they are pretty = most likely say yes 


To avoid demand characteristics, there are three techniques: 

  1. Naturalistic Observation -technique to gather info unobtrusively observing people in their natural environments 


  1. Privacy and Control -can’t be identified as the authors of their action, respond privately 


  1. Unawareness -people are are being observed are unaware of the true purpose of the observation 









Fast VS Slow Rat Study 

Psychology students measured how quickly rats learned a maze. Some students were told their rat was bred to be a slow learner, others a fast learner, though all rats were identical. Students expecting slow learners reported an average time of 3.47 minutes, while those expecting fast learners reported 2.35 minutes. The results reflected the students’ expectations rather than reality, for two reasons: 


  1. Expectations can influence observations 

  2. Expectations can influence reality 


This is called:

  • Observer bias = tendency for observers’ expectations to influence both what they believe they observed and what they actually observed


To avoid this, they use techniques (most common)

  • Double blind study = study in which neither the researcher nor the participant knows how the participants are expected to behave 



Description 


Population = complete collection of people 

Sample = partial collection of people drawn from a population 


Frequency distribution -graphic representation showing the number of times that the measurement of a property takes on each of its possible values 


Normal distribution -mathematically defined distribution in which the frequency of measurements is highest in the middle and decreases symmetrically in both directions 


Central tendency -descriptive statistics are statements about the value of the measurements that tend to lie near the centre or midpoint of the frequency distribution 


Mode - value of the most frequently observed measurement 


Mean -average value of all measurements


Median -value in the middle 

Variability: how wide is the distribution 


Variability = tells us how much the measurements differ from each other or roughly how “wide” the distribution is 


Range = value of the largest measurement in a frequency distribution minus the value of the smallest measurement  


Standard deviation = how each of the measurements in a frequency distribution differs from the mean