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1) Background Information Everything already known Everything already known
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Scientific Methodology:Scientific Methodology:Background Information,Background Information,
Questions, Research Questions, Research Hypotheses, the Hypothetico-Hypotheses, the Hypothetico-
Deductive Approach, and Deductive Approach, and the Test of Hypothesisthe Test of Hypothesis
BIOL457BIOL45720 January 201620 January 2016
2) Question2) Question Inspired by background info—there is always Inspired by background info—there is always somethingsomething as-yet unexplored and unknown as-yet unexplored and unknown
3) Research Hypothesis3) Research Hypothesis May (or may not) be true answer to questionMay (or may not) be true answer to question
4) Test of Hypothesis4) Test of Hypothesis Designed to attempt to falsify research Designed to attempt to falsify research
hypothesishypothesis May or may not be a controlled experimentMay or may not be a controlled experiment
5) Null Hypotheses5) Null Hypotheses Symbol: HSymbol: H00
Predictions of a lack of cause-and-effect in Predictions of a lack of cause-and-effect in data to be collecteddata to be collected
Typically several HTypically several H00’s for any one research ’s for any one research hypothesishypothesis
6) Statistical Conclusions6) Statistical Conclusions Each HEach H00 can either be… can either be…
……rejected, orrejected, or ……not rejected.not rejected.
(Notice lack of term “accepted”)(Notice lack of term “accepted”)
7) Conclusion7) Conclusion Do data and statistical conclusions…Do data and statistical conclusions…
……support research hypothesis?support research hypothesis? ……refute research hypothesis?refute research hypothesis?
8) Publication8) Publication Most commonly in a peer-reviewed journalMost commonly in a peer-reviewed journal Necessary to stimulate the cyclical nature of Necessary to stimulate the cyclical nature of
scientific methodologyscientific methodology One researcher’s data and conclusions serve as One researcher’s data and conclusions serve as
background information, inspiring another background information, inspiring another researcher’s question and/or research hypothesisresearcher’s question and/or research hypothesis
Three TypesThree Types
A) Personal observation [by author]A) Personal observation [by author]
Cited as: (pers. obs.)Cited as: (pers. obs.)
May also include author’s unpublished data that relate May also include author’s unpublished data that relate toto
the study, cited as: (A. Smith, unpubl. data)the study, cited as: (A. Smith, unpubl. data)
Three TypesThree Types
B) Personal communication [from another B) Personal communication [from another researcher]researcher]
Cited as: (A. Jones, pers. comm. 2001)Cited as: (A. Jones, pers. comm. 2001)
May also include colleague’s unpublished data that May also include colleague’s unpublished data that relaterelate
to the studyto the study
Three TypesThree Types
C) Cited literatureC) Cited literature
Four major types:Four major types:1) Peer-reviewed article1) Peer-reviewed article2) Book2) Book3) Book chapter in edited volume3) Book chapter in edited volume4) Unpublished Masters thesis or Ph.D.4) Unpublished Masters thesis or Ph.D.
dissertationdissertation
Peer ReviewPeer Review Choose a journalChoose a journal Send ms. to editorSend ms. to editor Commonly farmed out to associate editorCommonly farmed out to associate editor
Solicits 2-3 anonymous reviewsSolicits 2-3 anonymous reviews Ms. returned to authorMs. returned to author
A) Accept, following minor revisions based on reviewerA) Accept, following minor revisions based on reviewer commentscommentsB) May accept, following major revisionsB) May accept, following major revisionsC) “Thank you for considering our journal…”C) “Thank you for considering our journal…”
Timeline*Timeline* Research completedResearch completed Ms. submitted to editor a few to several months laterMs. submitted to editor a few to several months later
Generally, pre-review by 1-2 colleaguesGenerally, pre-review by 1-2 colleagues To anonymous reviewers within a monthTo anonymous reviewers within a month Back to author within a few months of submissionBack to author within a few months of submission Final acceptance a few to several months laterFinal acceptance a few to several months later Publication 6-18 months laterPublication 6-18 months later
May appear online soonerMay appear online sooner
*Much faster for *Much faster for NatureNature, , ScienceScience, certain biomedical journals, , certain biomedical journals, etc.etc.
The QuestionThe Question Inspired by background infoInspired by background info Seeks explanation of phenomenonSeeks explanation of phenomenon
The Research HypothesisThe Research Hypothesis PotentiallyPotentially correct answer to question correct answer to question
(Ergo, potentially (Ergo, potentially incorrectincorrect)) GeneralGeneral statement about nature, statement about nature, notnot one one
specific to conditions of the test to be specific to conditions of the test to be conductedconducted
May be…May be… ……strongly suggested by extensive prior theorystrongly suggested by extensive prior theory ……reasonable hypothesis based on previous studiesreasonable hypothesis based on previous studies ……a stab in the darka stab in the dark
FalsificationFalsification ““To prove”: once upon a time, this meant “to To prove”: once upon a time, this meant “to
test”test” Utah proving groundsUtah proving grounds Printer’s proofsPrinter’s proofs ““The exception that proves the rule”The exception that proves the rule”
Hypotheses can only be Hypotheses can only be disprovendisproven with with confidenceconfidence
Confidence that a hypothesis is correct comes Confidence that a hypothesis is correct comes with well-designed test(s) that fail to refute itwith well-designed test(s) that fail to refute it
Deductive ReasoningDeductive Reasoning Using several specific facts to build a general Using several specific facts to build a general
explanationexplanation Foundation for the Introduction section of a Foundation for the Introduction section of a
journal articlejournal article Discuss background info (lots of known specific Discuss background info (lots of known specific
facts)facts) Culminates in formulating research hypothesis Culminates in formulating research hypothesis
(general statement that may or may not explain a (general statement that may or may not explain a phenomenon)phenomenon)
Inductive ReasoningInductive Reasoning Assuming general explanation is true, using it Assuming general explanation is true, using it
to predict specific outcomesto predict specific outcomes Foundation for the Methods and Results and Foundation for the Methods and Results and
lead portion of Discussionlead portion of Discussion IfIf the research hypothesis is true, in a general way the research hypothesis is true, in a general way
in nature, in nature, ThenThen, one expects certain specific patterns in the , one expects certain specific patterns in the
data that are to be collecteddata that are to be collected
Data Collection and AnalysisData Collection and Analysis Independent Variable: hypothesized cause of Independent Variable: hypothesized cause of
some effectsome effect Dependent Variable: hypothesized effect of some Dependent Variable: hypothesized effect of some
causecause Hypothesized influence: IV Hypothesized influence: IV DV DV
Controlled ExperimentControlled Experiment Independent Variable: hypothesized cause of Independent Variable: hypothesized cause of
some effectsome effect Dependent Variable: hypothesized effect of some Dependent Variable: hypothesized effect of some
causecause Hypothesized influence: IV Hypothesized influence: IV DV DV Experimental treatment(s): receive(s) IVExperimental treatment(s): receive(s) IV Control treatment(s): do(es) not receive IVControl treatment(s): do(es) not receive IV Control variableControl variabless: held : held constantconstant between groups between groups
The Advantage of The Advantage of Controlled ExperimentationControlled Experimentation
Complete isolation of potential causative Complete isolation of potential causative variable (the IV)variable (the IV)
Otherwise, correlation of DV with IV may Otherwise, correlation of DV with IV may occur because…occur because… ……IV exerts influence on DV, orIV exerts influence on DV, or ……IV and DV are actually both influenced by a IV and DV are actually both influenced by a
separate variable not under studyseparate variable not under study