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# Open Universiteit Pls Prestation November 1st

## on Nov 02, 2012

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Lecture for the PhD School of the Open Universiteit at the premesis of Nyenrode Business University

Lecture for the PhD School of the Open Universiteit at the premesis of Nyenrode Business University

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## Open Universiteit Pls Prestation November 1stPresentation Transcript

• PLS Tutorial prepared for the PhD School November 1st, 2012 Dr. Paul Ghijsen Associate Professor Supply Chain ManagementDepartment Marketing and Supply Chain Management
• Preamble (1/2)• Tool/ technique. Not aim (for me)• Easy to use• Often applicable – real life / complex situationSuggestion is limited to the presentation of PLS-PM results for a manuscriptPLS Tutorial Paul Ghijsen November 1st 2012
• Preamble (2/2)• Add to existing literature …• Specific problem statement• Limited number of research questions• Force yourself to answer in one sentence : what is the topic of your research and what should the answer look like (in the end)…• Make a graph of the relationships -> conceptual model• Use literature to ‘compile’ questionnairePLS Tutorial Paul Ghijsen November 1st 2012
• Overview tutorial• Introduction SEM• Focus on Partial Least Squares – Especially SmartPLS, how to … • Specify the model • Derive results and • Present results• What you should think about• Where to get it PLS Tutorial Paul Ghijsen November 1st 2012
• Introduction to SEMPLS Tutorial Paul Ghijsen November 1st 2012
• A relatively simple modelPLS Tutorial Paul Ghijsen November 1st 2012
• Introduction to SEM• Factor-based covariance fitting approach for latent structural modeling: LISREL, AMOS.• Estimation methods: – Maximum Likelihood and – Generalized Least Squares / Generalized Method of Moments• SEM with causal diagrams involve three primary components: – Indicators (manifest variables or observed measures/variables) – latent variable (construct, concept, factor) – path relationships ( correlational, one-way paths, or two way paths). – Take a look at David A. Kenny’s overviewPLS Tutorial Paul Ghijsen November 1st 2012
• Reflective or formative indicators? • Latent or Emergent Constructs: Covary or not • Strong theory or not ?PLS Tutorial Paul Ghijsen November 1st 2012
• Introduction to SEM• All the measured variance is useful variance to be explained. A general model which encompasses, among other techniques, canonical correlation, redundancy analysis, multiple regression, multivariate analysis of variance, and principal components• Sample size can be smaller: strong rule of thumb: equal to the larger of the following: (1) ten times the scale with the largest number of formative (i.e., causal) indicators, or (2) ten times the largest number of structural paths directed at a particular construct in the structural model.PLS Tutorial Paul Ghijsen November 1st 2012
• Focus on Partial Least Squares • Powerful method of analysis because of the minimal demands on measurement scales, sample size, and residual distributions. • PLS is considered better suited for explaining complex relationships (Editorial LRP 2012)PLS Tutorial Paul Ghijsen November 1st 2012
• Steps to publish your results• Download your data• Data preparation or ‘cleaning’ your data• Compute data descriptions using e.g. SPSS (table 1) – Focus on Mean, STD, Skewness and Kurtosis• Report on reliability test (Cronbach’s alpha) (table 2)• Draw your inner model and your outer model• Analyse the results from the PLS algorithm, Bootstrapping, FIMIX• Use info on factor loadings and t-values to complete table 1 (outer model)• Check convergent and discriminant validity• Present table 4 on the results of the inner (or structural) modelPLS Tutorial Paul Ghijsen November 1st 2012
• Steps to prepare your dataStep 1 Download the dataset in Spss formatStep 2 Replace values 8888888 & 9999999 with sysmis (.)Step 3 Recode control questionsStep 4 Replace the sysmis with series means Step 5 Compute Cronbach’s alpha for the (existing) dimensions ( >.70)Step 6 Delete (old) variables and / or respondents (with extreme care)Step 7 Save file as tab-delimted“ or .csvPLS Tutorial Paul Ghijsen November 1st 2012
• Compute descriptives• Focus on – Mean – Standard deviation – Skewness – Kurtosis• Possibly correlations• E.g. use SPSSPLS Tutorial Paul Ghijsen November 1st 2012
• Compute Reliability results • Compute Cronbach’s alpha – >= 0.6 for new variables – >= 0.7 for existing variablesPLS Tutorial Paul Ghijsen November 1st 2012
• Especially SmartplsPLS Tutorial Paul Ghijsen November 1st 2012
• Conceptual modelInfluence of customer orientation on salesperson performance PLS Tutorial Paul Ghijsen November 1st 2012
• Conceptual modelInfluence of customer education, expertise and experience on customer loyaltyPLS Tutorial Paul Ghijsen November 1st 2012
• Convergent and discriminant validity• Convergent: • AVE >= 0.5• Discriminant: • Square root of AVE >= correlations (row and column)PLS Tutorial Paul Ghijsen November 1st 2012
• Goodness of Fit of the models• FIMIX procedure in SmartPLS: – Akaike Information Criterion (Analogous to Chi-square) – Baysian IC (id.) – Corrected AIC (id.) – ENtropy, close to 0.5PLS Tutorial Paul Ghijsen November 1st 2012
• The SmartPLS tutorial videos• http://youtu.be/-jegL4d-MXk Drawing a basic model• http://www.youtube.com/watch?v=vNI7Cc48nRg Estimating the basic PLS path model• http://www.youtube.com/watch?v=DX_OLuuP7lo Bootstrapping, p-values• http://www.youtube.com/watch?v=juGqAMXKkZQ Epilogue• http://www.youtube.com/watch?v=kalTHr8EKC0 How to handle missing data• http://www.youtube.com/watch?v=acAl78zCqPU Basic concepts of PLS path modeling• http://www.youtube.com/watch?v=RAL9X17r7CE PLS Path Modeling or Co-variance SEM• WARPPLS:• http://www.youtube.com/watch?v=yUojJaV3jlAPLS Tutorial Paul Ghijsen November 1st 2012
• What you should think about• PLS is not a silver bullet: – SEM co-covariance techniques also matter. – Inadmissable solutions – Factor indeterminancy• Look at distribution of your data: ‘feel your data’.• Aim for adequate data collection (adequate sample size)PLS Tutorial Paul Ghijsen November 1st 2012
• Where to get it?• SmartPLS via www.smartpls.de• PLSgraph via Wynne Chin (wchin@uh.edu ; http://disc- nt.cba.uh.edu/chin/indx.html )• WarpPLS via www.nedcock.com• R via http://georgia-r-school.org/PLS Tutorial Paul Ghijsen November 1st 2012
• Additional resources (1/3)PLS Tutorial Paul Ghijsen November 1st 2012
• Additional resources (2/3)PLS Tutorial Paul Ghijsen November 1st 2012
• Additional resources (3/3) Online courses or classes: - http://georgia-r-school.org/ - http://www.school.smartpls.com/PLS Tutorial Paul Ghijsen November 1st 2012