Dear Colleagues,
I'm working on a Delphi study comparing perceptions of high school technology teachers and university engineering educators about the importance of concepts about engineering for HS students to learn as part of their fundamental education. I'm actually doing this as part of my Ph.D. The survey items (n=37) are categorized into five scales: design, human values, modeling, resources, and systems thinking. I'm seeking to determine the reliability of these scales and of the overall survey instrument. Since I'm working with ordinal data, Chronbach's Alpha probably isn't the best statistical tool to use. I've literally spent several days learning my way around R-project but am struggling with procedures and interpretations. I'm aware that there is now a plug-in for R for SPSS that can be downloaded ( <http://www-01.ibm.com/support/docview.wss?uid=swg21477550> http://www-01.ibm.com/support/docview.wss?uid=swg21477550 and <http://gruener.userpage.fu-berlin.de/Essentials%20for%20R%20Installation%20 Instructions_21.pdf> http://gruener.userpage.fu-berlin.de/Essentials%20for%20R%20Installation%20I nstructions_21.pdf). Just learned that today and I downloaded PolyCorrelations.zip from https://www.ibm.com/developerworks/community/files/app?lang=en#/file/9f47f9a 0-7793-4ad5-8bb7-d3fd1a028e44 I've gotten as far as loading Rcmdr and running some analyses - (Statistics, dimensional analysis, scale reliability) and I've generated this output: Reliability deleting each item in turn: Alpha Std.Alpha r(item, total) design 0.8445 0.8490 0.7629 humanvalues 0.8526 0.8541 0.7170 modeling 0.8511 0.8546 0.7271 resources 0.8712 0.8757 0.6328 systems 0.8461 0.8498 0.7488 I now would sincerely appreciate some help. At the age of 70, never having studied programming, the meaning of these statistics is not apparent. For example, I'm not clear if either of these three statistics are Ordinal Alpha. Since I'm working with Likert scale items, my advisor suggested that I seek an alternative to Chronbach's Alpha to determine reliability. So far, here are the steps I have taken: I've searched the FAQs Searched specifically for answers on the Web Played with the software for hours Read the accompanying documentation. Downloaded and installed Rcmdr Downloaded and installed PolyCorrelations. I tried running PolyCorrelations but I get a message that states that this requires the Polychor and Gclus libraries. I tried to install them into the R console, but no luck. I'd also be pleased to work with someone-on-one on a consulting basis if someone has the time and inclination. Hoping to find an individual who knows SPSS and R. Thanks very sincerely for considering this request. Michael -------------------------------- END OF MESSAGE -------------------------------- Michael Hacker, Co-Director Hofstra University Center for STEM Education Research Ph: 518-724-6437 Cell: 518-229-7300 Fax: 518-434-6783 URL: www.Hofstra.edu/CSR [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
