1Introduction to Research &Design of Experiments2Scientific MethodPropose Hypothesis (Based on Theory)Collect and Analyze DataTest Hypothesis (Statistical Analysis)Confirm / Deny HypothesisExplain DiscrepanciesReport Conclusions3ResearchIntroduction to ResearchDefinition and PurposeResearch CycleStructure of a Research ProjectTypes of ResearchDescriptiveExperimental4Research - Definition and PurposeProcess - Systematic, Organized, LogicalInvestigation of nature and natural phenomenaPurpose -Develop UnderstandingDiscover TruthsAscertain “What Causes What”Leads to unequivocal interpretations/generalizations.Helps choose and decide upon one hypothesis from among equally plausible hypotheses.5ResearchResearch CANNOT prove a hypothesis; however it helps disprove (disaffirm) alternate hypotheses and helps build a cumulative body of corroborating evidence in support of the primary hypothesis.6Research Cycle1. Observation2. Theory Formulation -Statement of Research Hypotheses3. Research and Data Collection4. Statistical Analyses5. Reporting7Research Cycle - continued1. ObservationLiterature Search, Own ResearchNatural Setting, Laboratory Environment2. Statement of Research HypothesisSupported by Theoretical BasisStated in Specific TermsTestable ScenarioPredictive Results8Research Cycle - continued3. Data Collection Study, Experiment, Clinical ObservationsData Collected and Recorded4. Statistical AnalysesDescriptive StatisticsInferential StatisticsParameter EstimationNull Hypothesis TestingResearch Hypothesis Supported or Refuted9Research Cycle - continued5. ReportingWrittenReviewedPresentedPublishedReplicated10Structure of a Research ReportIntroductionMethodologyAnalysis (Results)DiscussionSummaryLimitationsConclusionsRecommendations11Research Report - continuedIntroductionProblem AreaLiterature ReviewProblem StatementVariables (Independent and Dependent)Hypotheses12Research Report - continuedMethodologySubjectsExperimental DesignOperational DefinitionsTreatmentsApparatusInstrumentationStimuliTechniquesProcedures13Types of ResearchDescriptive ResearchExperimental Research14Descriptive ResearchDescribes differences based on observations.May be used to suggest possible causation agents.Cause and Effect conclusions are NOT supported.Descriptive Research CANNOT and DOES NOTprove anything !!!!15Types of Descriptive ResearchSurveyCase StudyDevelopmentalTrend AnalysisLongitudinal StudiesCross-Sectional StudiesCausal Comparative (Correlational, Ex Post Facto)16Experimental ResearchControls the experimental environment -Helps discover cause and effectManipulates (Controls) the Independent variable (Treatment)Do what, to whom, how much, how oftenwhere, when, etc, etc, etc.Observe the effects on theDependent variable (Response)Draw conclusions about the extent of the cause and effect relationship.17“Design of Experiments”Producing Meaningful DataSampling TheoryRandom SamplingStatistical InferenceSampling DesignsPrinciples of Experimental DesignRandomizationConfounding VariablesReplication and Repeatability18Producing Meaningful DataWhy Sample - Faster, Cheaper, EasierMeaningful data, not just numbersWhat needs to be measuredHow should it be measuredWhat are the variablesExperimental Design addresses the followingHow many subjects, how to select, how to groupHow many trialsHow to analyze the results19Sampling TheorySubjects randomly selected andrandomly assigned to different treatment levels.Any characteristics (differences) that are present in the population, will be proportionally distributed in a random sample, thereby canceling any bias between the groups (treatment levels).Any differences between the groups, will be due to the effects of the different treatments themselves and not do to any differences between individual subjects.20Random SamplingChance is deliberately used in statisticalsampling, experimentation, and analysis.Chance helps eliminate bias andhelps assure a representative sample.Bias controlled by randomization.Variability controlled by sample size.21Statistical InferenceMaking InferencesDrawing ConclusionsGeneralizingabout a population based on sample data.Estimate the value of a population parameter using the value of a sample statistic.Form a conclusion about a population in general based on a specific sample characteristic.22Principles of Experimental DesignRandomization (Bias & Variability)Control of or Accounting for theEffects from Confounding (Extraneous) VariablesReplication and Repeatability (Validity & Reliability)23RandomizationCompletely Randomized (Between Subjects) Design- All subject participate in only one treatment level.Repeated Measures (Within Subject) Design- All subjects participate in all treatment levels.Mixed Factorial (Blocked or Nested) Design- Subjects are grouped according to some common characteristic, then participate in all remaining treatment conditions.24Confounding VariablesHistoryMaturationInstrumentationTestingRegressionSelectionMortalityInteraction of Testing with the Experimental VariableInteraction of Selection with the Experimental VariableReactive Effects of the Experimental EnvironmentMultiple Treatment Effects25Replication &