Chapter 04 Introduction to quantitative research

Introduction to quantitative researchChapter 4 What is Quantitative researchQuantity is the unit of analysisAmountsFrequenciesDegreesValuesIntensityUses statistics for greater precision and objectivityBased on the deductive modelConceptualizing quantitative researchOverall purpose or objectiveResearch literatureResearch questions and hypothesesSelecting appropriate methodsValidity and reliability of the dataFoundation for quantitative researchConcept Abstract thinking to distinguish it from other elementsConstruct Theoretical definition of a concept; must be observable or measurable; linked to other conceptsVariable Presented in research questions and hypothesesOperationalization Specifically how the variable is observed or measuredHypotheses for quantitative researchEducated guess or presumption based on literatureStates the nature of the relationship between two or more variablesPredicts the research outcomeResearch study designed to test the relationship described in the hypothesisTypes of research hypothesesDirectional hypothesisPrecise statement indicating the nature and direction of the relationship/difference between variablesNondirectional hypothesisStates only that relationship/difference will occurAssessing hypothesesSimply stated?Single sentence?At least two variables?Variables clearly stated?Is the relationship/difference precisely stated?Testable?Null hypothesesImplicit complementary statement to the research hypothesisStates no relationship/difference exists between variablesStatistical test performed on the nullAssumed to be true until support for the research hypothesis is demonstratedRemember that --Hypotheses are always tentativeResearch hypothesis, not the null hypothesis, is the focus of the research and presented in the research reportResearch questions for quantitative researchPreferred when little is known about a communication phenomenonUsed when previous studies report conflicting resultsUsed to describe communication phenomenaA variable -- Is an element that is identified in the hypothesis or research questionIs a property or characteristic of people or things that varies in quality or magnitude Must have two or more levelsMust be identified as independent or dependentIndependent variableManipulation or variation of this variable is the cause of change in other variablesTechnically, independent variable is the term reserved for experimental studiesAlso called antecedent variable, experimental variable, treatment variable, causal variable, predictor variableDependent variableThe variable of primary interestResearch question/hypothesis describes, explains, or predicts changes in itThe variable that is influenced or changed by the independent variableIn non-experimental research, also called criterion variable, outcome variableRelationship between Ivs and DVsCannot specify independent variables without specifying dependent variablesNumber of independent and dependent variables depends on the nature and complexity of the studyThe number and type of variables dictates which statistical test will be usedOperationalizing variablesAll variables need an operationalizationMultiple operationalizations exist for most variablesSpecifies the way in which variable is observed or measuredPractical and useful?Justified argument?Coincides with the conceptual definition?Why choose quantitative research?AdvantagesLimitationsTradition and history implies rigorNumbers and statistics allows precise and exact comparisonsGeneralization of findingCannot capture complexity of communication over timeDifficult to apply outside of controlled environmentsIssues of reliability and validityReliability = consistency in procedures and in reactions of participantsValidity = truthDoes it measure what it intended to measure?When reliability and validity are achieved, data are presumed to be free from systematic errorsThreats to reliability and validityIf measuring device cannot make fine distinctionsIf measuring device cannot capture people/things that differWhen attempting to measure something irrelevant or unknown to respondentCan measuring device really capture the phenomenon you want to investigate?Sources of variationVariation must represent true differencesOther sources of variationFactors not measuredPersonal factorsDifferences in situational factorsDifferences in research administrationNumber of items measuredUnclear measuring deviceMechanical or procedural issuesStatistical processing of data