Thinking Critically, What is Science? Psychology 1106

Introduction What is science? What is science? Guys in lab coats?Guys in lab coats? Test tubes?Test tubes? Hmmmmmmm Hmmmmmmm Well, more than anything, science is a method of inquiry Well, more than anything, science is a method of inquiry There are many ways to ‘seek the truth’ There are many ways to ‘seek the truth’

Conventional Wisdom or Common Sense If most people say or think something is true it is If most people say or think something is true it is Basically what gets us through everyday life Basically what gets us through everyday life Old sayings Old sayings There are many contradictory onesThere are many contradictory ones I don’t need any of your fancy science to understand human behaviour science boy. I don’t need any of your fancy science to understand human behaviour science boy. Umm, that’s Dr. Science Boy…Umm, that’s Dr. Science Boy…

Conventional Wisdom ‘Intuitive physics’ ‘Intuitive physics’ Male-female differences in cognition Male-female differences in cognition ‘Crime is increasing’ ‘Crime is increasing’ ‘The world is flat’ ‘The world is flat’ So, conventional wisdom or common sense, except for things like ‘I should wear pants’ is pretty much useless So, conventional wisdom or common sense, except for things like ‘I should wear pants’ is pretty much useless

Religion Belief based on faith Belief based on faith Seems to be designed for dealing with the metaphysical Seems to be designed for dealing with the metaphysical Why are we hereWhy are we here What does it all meanWhat does it all mean One does not usually believe in God because of some bit of evidence or rigorous experimentation One does not usually believe in God because of some bit of evidence or rigorous experimentation It is called faith for a reason It is called faith for a reason

Legal Method Getting at the truth based on the presentation of evidence Getting at the truth based on the presentation of evidence Not all evidence is admissible Not all evidence is admissible Fairness is the key Fairness is the key System is weighted System is weighted Sometimes your defense is as good as your lawyer Sometimes your defense is as good as your lawyer

Legal method Laws are based on what society sees as fair Laws are based on what society sees as fair At one time the law said it was ok to smoke in public buildings At one time the law said it was ok to smoke in public buildings We decided that it no longer was We decided that it no longer was Try doing that with oh, Newton’s second law… Try doing that with oh, Newton’s second law…

Scientific Method Takes a bit from each method Takes a bit from each method Used for a certain set of problems Used for a certain set of problems For specific reasons too For specific reasons too Started really in the late 1600s or so, Newton, Bacon and others Started really in the late 1600s or so, Newton, Bacon and others

Characteristics of Scientific thinking Empiricism Empiricism Direct observation and experimentationDirect observation and experimentation Objectivity Objectivity Rely on measurementRely on measurement Carefully controlled measurementCarefully controlled measurement No bias No bias Take results at face valueTake results at face value

Characteristics continued Testability Testability Popper’s falsifiability principlePopper’s falsifiability principle Predictions drawn from a theory must be specific enough to allow the theory to be shown to be incorrect

Even more characteristics Feasibility Feasibility Science deals with questions that are answerable using experimentationScience deals with questions that are answerable using experimentation Skepticism Skepticism Don’t believe it until you see itDon’t believe it until you see it Just because something seems right does not make it soJust because something seems right does not make it so People who do not know what they are talking about see this as weakness of sciencePeople who do not know what they are talking about see this as weakness of science It is a strength, peer review is skepticism in practice It is a strength, peer review is skepticism in practice

Key terms Hypothesis Hypothesis Statement about the relationship of variablesStatement about the relationship of variables Independent variable Independent variable What you manipulateWhat you manipulate Experimenter controlledExperimenter controlled Dependent variable Dependent variable MeasuredMeasured Note, there can be more than one IV and more than one DV Note, there can be more than one IV and more than one DV Operational Definition Operational Definition Defining a construct solely based on the operations used to measure itDefining a construct solely based on the operations used to measure it

Key Terms - Theory We tend to say ‘just a theory’ like it’s a hunch We tend to say ‘just a theory’ like it’s a hunch It is different in science It is different in science A set of statements that explain a variety of occurrences A set of statements that explain a variety of occurrences A good theory makes predictions, organizes data and is testable A good theory makes predictions, organizes data and is testable Theories change when new data show up to challenge them Theories change when new data show up to challenge them You CANNOT prove a theory, you can only disprove it You CANNOT prove a theory, you can only disprove it

More terms, more excitement!!!! Deduction Deduction Going from theory to dataGoing from theory to data Induction Induction Going from data to theoryGoing from data to theory Tend to be more limitedTend to be more limited Deduced ones are broaderDeduced ones are broader Still the good ones are precise Still the good ones are precise

Testing theories We test theories with many methods We test theories with many methods Correlational research Correlational research Measure two variables, see if they are relatedMeasure two variables, see if they are related ExamplesExamples More smokes, more cncer More smokes, more cncer More IQ more money More IQ more money Which way do they go? Which way do they go? Impossible to tellImpossible to tell

CORRELATION IS NOT CAUSATION

Observational Research Not just watching stuff happen Not just watching stuff happen Careful measurements Careful measurements Still use operational definitionsStill use operational definitions Examples Examples Rosenhan (1975) ‘On being sane in insane placesRosenhan (1975) ‘On being sane in insane places Turnbull (1987) ‘ The Forest People’Turnbull (1987) ‘ The Forest People’

Experimentation Have independent and dependent variables Have independent and dependent variables Manipulate IV, measure DV Manipulate IV, measure DV Control groups Control groups Double blind procedures Double blind procedures

Making Causal Inferences To say that X causes Y we need three things: To say that X causes Y we need three things: Temporal precedenceTemporal precedence CovariationCovariation Elimination of alternative explanationsElimination of alternative explanations When we have an alternative explanation we call it a confound When we have an alternative explanation we call it a confound These can be avoided with careful design These can be avoided with careful design

Ethics Research must be ethical Research must be ethical Informed consent Informed consent No coercion No coercion No deception unless necessary No deception unless necessary Debriefing Debriefing There is a well established set of rules There is a well established set of rules