Sampling Issues in Research

Planning an Applied Research Project Chapter 8 – Sampling Issues in Research© 2014 John Wiley & Sons, Inc. All rights reserved.Learning ObjectivesExplain the reasons for samplingDistinguish between probability and non-probability sampling methodsSelect an appropriate sampling procedureExplain the types of sampling biasAvoid sampling bias in your research designs now and in the future© 2014 John Wiley & Sons, Inc. All rights reserved.Key TermsAcquiescence biasAnalytic process errorsArea samplingAuspices biasCluster samplingConfidence level Convenience sampling Destructive samplingDouble samplingExtremity biasIntercept samplingInference errorsInternet samplingInterpretation errorsInterviewer interaction biasJudgmental samplingModerating variablesNon–probability samplingNon-response biasQuota sampling© 2014 John Wiley & Sons, Inc. All rights reserved.Key Terms(cont’d)PrecisionProbability samplingPurposive samplingProportional stratified samplingRecording errorRelevant sampleRespondent biasSample frameSample selection processSample sizeSimple random samplingSnowball samplingSocial desirability biasStratified random samplingSystemic biasSystemic bias errorsTarget sample© 2014 John Wiley & Sons, Inc. All rights reserved.Reasons for SamplingS StaffT TimeE EfficiencyA AccuracyM Money or Resources© 2014 John Wiley & Sons, Inc. All rights reserved.Strategies for Selecting a SampleProbability samplingNon-probability samplingInternet sampling© 2014 John Wiley & Sons, Inc. All rights reserved.Probability Sampling StrategiesArea samplingCuster samplingDouble samplingProportional stratified random samplingSimple random samplingStratified random sampling© 2014 John Wiley & Sons, Inc. All rights reserved.Non-Probability Sampling StrategiesConvenience samplingDestructive samplingIntercept samplingPurposive or judgmental samplingQuota samplingSnowball sampling© 2014 John Wiley & Sons, Inc. All rights reserved. Sources of Sample BiasThree Forms of Bias Systemic biasRespondent biasInterviewer bias© 2014 John Wiley & Sons, Inc. All rights reserved.Systemic BiasAnalytic process errorsModerating variablesSystemic bias© 2014 John Wiley & Sons, Inc. All rights reserved.Respondent BiasAcquiescence biasAuspices biasExtremity biasNon-response biasSocial desirability bias© 2014 John Wiley & Sons, Inc. All rights reserved.Interviewer BiasInference errorsInterviewer interaction biasInterpretation errorsRecording errors© 2014 John Wiley & Sons, Inc. All rights reserved.Sample SizePurpose of the researchLevel of confidence neededExtent of precision required or desired© 2014 John Wiley & Sons, Inc. All rights reserved.Review of Class SessionAnything unclear?One thing that I learned from this class is © 2014 John Wiley & Sons, Inc. All rights reserved.