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Published byHarry Hancock Modified over 8 years ago
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What is Science?
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Objectives What is Science? Areas of Scientific Research Basic vs. Applied Research Why understand Science? The Philosophy of Science –Scientific statements –Scientific methodology –What are: Hypotheses Theories Facts
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Science More simply: Science is the acquisition of reliable but not infallible knowledge of the real world, including explanations of phenomena. Oxford Dictionary definition: A branch of knowledge conducted on objective principles involving the systematized observation of and experiments with phenomena, especially concerned with the material and functions of the physical universe
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What Science is not! (popular myths) 1.The practice of Science leads to the truth. 2.Science can prove things 3.Science can only be done whenever experimental manipulation can be carried out. The essence of Science is the testability of hypotheses.
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Knowledge comes in many forms Science is one approach to gaining knowledge through research Science includes anything observable in the universe –Must be measurable –Empirical - relies on observation and experience
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Areas of Science Physical Sciences –Chemistry –Physics Biological Sciences –Ecology –Evolution –Molecular Biology Behavioural Sciences –Animal behaviour –Human behaviour Earth Sciences Can rely heavily on observation outside the laboratory
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Basic vs. Applied Science Basic Research –Driven by curiosity of researcher –Primarily done at Universities and Government institutes –E.g. Nuclear Physics, Ecology of Algae Applied Research –Done to solve a particular problem often leads to new or improved technology –E.g. Nuclear reactors, weapons etc., How to prevent algal blooms. These fields are intertwined; applied research relies heavily on basic research Push from governments and public to make research more applied... Is this a good idea?
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Why understand science? To be informed To make decisions Pseudoscience –Silly to dangerous –Need to separate sense from nonsense
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What about Science in the media or advertising? See if you can’t find something where “science” or “scientific” words are being used to sell things
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Why we need to understand Link between MMR vaccine & Autism 1998 Study in The Lancet –Sample size of 12 children –Parents of 8 noted symptoms of Autism after vaccination –Study recommended further investigation to examine possible link Press conference with lead author who suggested a link - Major health scare Children getting MMR vaccine dropped considerably
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Flaws with study –Small sample size –Patients were not chosen randomly –No control group Most importantly, despite these flaws the study did not observe a link Lead author –Received large amounts of money from lawyers –Applied for patent for a vaccine to rival MMR –As a result 10 of the 12 authors published a retraction Since then… All following studies have been definitive on the conclusion that there is no link between MMR vaccine and autism
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Decision Making & Science Swine flu is a good example What went through my head? –Cost/Benefit analysis –Success rate of past vaccines, risks –My/family health –Data on pandemic –Past H1N1 events (eg 1954)
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Philosophy of Science: The Scientific Method Philosophy How we understand the world Science A method for understanding Developing a theory Formulation of Hypotheses Predictions Design, Analyses How we test predictions Statistics Tools for testing
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Four Terms That Have Different Meanings in Science than in Ordinary Every Day Use: Fact Law Hypothesis Theory
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From the National Academy of Sciences: A Fact In science, an observation that has been repeatedly confirmed and for all practical purposes is accepted as “true.” Truth in science, however, is never final, and what is accepted as a fact today may be modified or even discarded tomorrow.
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From the National Academy of Sciences: A Law In Science, a descriptive generalization about how some aspect of the natural world behaves under specified circumstances. eg the second law of thermodynamics
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From the National Academy of Sciences: A Scientific Hypothesis A tentative statement about the natural world leading to deductions or predictions that can be tested. If the deductions are verified, it becomes more probable that the hypothesis is correct. If the deductions are incorrect, the original hypothesis is abandoned or modified.
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From the National Academy of Sciences: A Theory, The Goal of Science In science, a well substantiated explanation of some aspect of the natural world that incorporates facts, laws, and tested hypotheses. A Key element of Scientific theories is that they must be FALSIFIABLE
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Hypothesis Testing Comprises Much of What Scientists Do
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Null Hypotheses Null hypothesis –Expected outcome if supposed mechanism is not manifested –E.g. Hypothesis: Echinacea reduces the severity and duration of a cold Null hypothesis: Echinacea has no effect on the duration and severity of a cold Predictions –Expected outcomes if both assumptions and suppositions are correct.
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Inductive vs. Deductive Inductive reasoning –The inference of a general law from particular instances –Data Collection - Analysis - Theory –E.g. Darwin’s study of the Galapagos Finches Deductive reasoning –The inferences of particular instances from a general law –Body Theory - Data Collection - Analysis –Research is typically done this way now
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Let’s look at this a bit closer Induction: Every swan I have seen is white, therefore all swans are white If (particular observation), then (universal inference) Deduction: All swans are white, therefore the next swan I see will be white If (universal inference), then (particular observation) Which of the above is more testable? What if the next swan is black? Which do we typically use everyday? Which is more repeatable?
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More on Hypotheses Crucial to Science is hypothetic-deductive reasoning Statement of a hypothesis –A deduction (consequence/prediction) is made from the hypothesis and this is then tested Falsification of prediction falsifies the hypothesis HOWEVER, verification of prediction does not verify the hypothesis –In formulating hypotheses, scientists attempt to derive the simplest possible explanation that accounts for the data = Occam’s razor or Parsimony Propositions that are not falsifiable (subject to rejection) are NOT Scientific
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Hypotheses cont. Can you ‘prove’ a hypothesis to be true? Progress is made by repeated testing (rejection or confirmation) of alternative hypotheses until all reasonable ones have been tested. If you examine 1 million swans and observe them all to be white, does not prove the hypothesis that all swans are white - if you see one black swan, the hypothesis is falsified - falsification
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Circular Hypotheses Hypotheses cannot be tested if they are circular - What does this mean? –Is when an event/phenomena becomes the explanation for the event/phenomena –E.g. The company Applied Biosystems applies for many patents because it is innovative Scientific progress can ONLY be made if a hypothesis is open to being disproved Research hypotheses must refer to concepts that can be studied scientifically (can be observed) –Living organisms are purposely designed by a maker: no way to test for this hypothesis
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Evidence Hypotheses are usually tested through experimentation Two types of evidence accepted by scientists –Confirmation of hypotheses by data strengthens their validity –Repeated inconsistency of data with a hypothesis leads to rejection When a hypothesis is not verified, ask: is it because the hypothesis is incorrect or is it because of problems in the statement of the hypothesis, or problems in the experiment Repeat testing in many different ways
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Hypothetico-deductive reasoning Insight 1. Conception Problem Idea Previous observ. Existing theory General Hypothesis Specific Hypothesis 2. Assessment Comparison with new Observations or experimental results FalsificationConfirmation
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Experimental Research Process 1.Observations about the world or phenomena 2.Formulate a hypothesis 3.Devise predictions 4.Conduct an experiment 5.Draw conclusions, make revisions 6.Future experimentation
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Simple example 1.Observation Individuals taking Echinacea say that it reduces the intensity and duration of a cold 2.Hypothesis Echinacea reduces the severity & duration of a cold Null: Echinacea has no effect on the duration or severity of the common cold
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3.Testable predictions If Echinacea reduces the duration & severity then… Individuals taking Echinacea should get sick less frequently and should recover more quickly. 4.Conduct an Experiment Experimental group Treatment before exposure Treatment after exposure Evaluation Placebo Echinacea No treatment Exposure to cold virus Measure symptoms/duration Echinacea
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5.Draw conclusions All individuals from all four groups are just as likely to develop a cold Cold symptoms lasted for the same amount of time Echinacea had no effect on the duration or severity of the cold What next?
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Misconduct in Science
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Unfortunately, it happens. Why? Extreme example: –Woo Suk Hwang –South Korean Scientist –Papers published in Science in 2004, 2005 on stem cell clones –Seoul National University submitted report stating it was based on fraudulent data
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Fraud Fabrication of data –Making up information to support a result –Editing images –e.g. Hwang Falsification of data –Exclusion of data that does not support theory or hypothesis
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Plagiarism Use of someone else’s words or ideas without proper credit Original work must be cited, unless it is something that is widely known –e.g. DNA is transcribed into RNA and then translated to a protein Famous case of Elias Alsabti (1970’s)
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Questionable Research Practices Failing to retain data Inadequate research records Refusing to give peers access to material –Specimens –Sequences –Data sets Inappropriate statistics used to “inflate” data Exploitation of students or inadequate supervision Misrepresenting speculation as fact Selective reporting Interference
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Research on Humans and Animal Subjects Strict controls and review boards on campuses Weigh the value of the research (benefits) against the pain/discomfort of subjects - Is it necessary?
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Consequences Career can be over Punishment through community –Rejection of papers –Rejection of grants Integrity is key to being a good scientist!!!
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Pseudoscience How to Read Character: A New Illustrated Hand-Book of Phrenology and Physiognomy, for Students and Examiners; with a Descriptive Chart. (New York, Fowler & Wells Co., Pubs., 1891).
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A few words on: Pseudoscience Ideas often put forward as scientific when they are not Examples –Astrology –Creation Science/ Intelligent Design Theory –Paranormal phenomena –UFOs –Cryptozoology: eg Bigfoot, the Ogopogo and Loch Ness Monster –And many many many more…. Can be dangerous
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How to recognize Pseudoscience Driven by cultural, ideological or commercial goals Changed very little since first established Challenge to dogma is considered heresy Observations not consistent with beliefs are ignored Vague and ambiguous
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