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The Great Experiment
If you know UML you can help to provide data for comparing ORM with ER & UML by completing one of the experiments listed on this page.
 
Survey results
An interim report of the "Design or description" survey was posted to the Library on 24 May 2008. The surveys section of this library is open to registered members of this website. Registration is free. To register, just click on the "Join" button at the top right hand side of your screen.  

Survey 1: Is data modeling a descriptive process or a design process?
Descriptive tasks are based on the assumption that the "something" that you are to describe already exists. On the other hand, design is a creative task and there is no presumption of a pre-existing "something".
  
Dr Graeme Simsion believes that the answer to the "Describe or design?" question sets the context for data modeling. Is the Universe of Discourse (UoD) a reality that is "out there" just waiting to be described by the data modeler or is the UoD a reality that is created during the data modeling process? In 2007, Dr Graeme Simsion published the results of his PhD research in the book "Data Modeling: Theory and Practice". (For details of the book, just click on the image below ). Dr Simsion has kindly agreed to allow his work to be used as the basis of one or more surveys.
 
You may visit the Survey forum and vote on the question. "Is data modeling a descriptive process or a design process?"  

Books: Click an image for details
 

Survey & Experiment

The work mentioned on this page was originally designed to support my dissertation project for the award of a Master of Science Degree in Information Systems Management from Liverpool University. However, although my dissertation project was completed on 28 August 2008, the experiment remains open for anyone who chooses to participate because more contributors will help to improve the statistical significance of the results.

Is ORM more effective than other methods? Many people claim that ORM is more effective than other methods. However, to the best of my knowledge, until now,  there has never been a scientific investigation into this claim. So this experiment is designed to test the hypothesis that "ORM is at least 25% more effective than ER and UML"

5 September 2008: The initial experiment was completed in August 2008 and the results were included as part of my MSc Dissertation document. However, the briefing packages remain active and anyone with appropriate skills is invited to contribute.

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The Experiment aims to provide data to test the hypothesis that ORM is at least 25% more effective than approaches based on either ER or UML. The experiment is managed via this website but the experiment itself is conducted by volunteers with appropriate expertise.

The experiment provides a standard input text that uses just 331 words to describe some of the functions in an imaginary airline. The idea of the experiment is for each participant to convert the 331 words into a UML "data only" class diagram using just one of the three methods described in the briefing packages. 
 
All three experimental packages require that the person who does the experiment has sufficient UML skill to create a UML "data only" class model. The differences between the packages are explained below.
 
UML briefing package: This package is for people who have UML skills. This procedure asks that you use the "standard UML approach" defined at  http://www.ibm.com/developerworks/rational/library/5383.html . This approach requires that you begin by creating UML use case(s) and then use the UML use cases to create a UML "data only" class model. 
Click for the UML briefing package
ER briefing package: This package is for people with both ER and UML skills. This procedure asks that you use any ER technique to create an ER model and then convert the ER model to a UML "data only" class model. 
Click for the ER briefing package
ORM briefing package:  This package is for people with both ORM and UML skills. This procedure asks that you use one of three popular ORM tools (VisioModeler, VEA or NORMA) to create an object-role model and then convert the object-role model to a UML "data only" class model. The briefing document contains a summary of the ORM to UML conversion procedure that is explained on page 389 of Terry's "Big Brown Book" (Information Modeling and Relational Databases: Second Edition, Halpin & Morgan 2008). However, you can use any ORM-UML conversion method that you prefer. 
Click for the ORM briefing package
Each of the foregoing procedures has a link to a separate online questionnaire that allows participants to post their results directly into an online database.
 
All results are anonymised. No personal details were revealed in my dissertation document or will be revealed to any third party. 
 
14 November 2008: Dissertation Results 
I submitted my dissertation document on 28 August 2008. Two independent assessors from Liverpool University graded my work. In early November 2008, my dissertation was graded "A" by the Liverpool University Board of Examiners and I received an overall distinction for my MSc work.   
 
I would like to thank those persons who contributed to my experiment.

Ken Evans
© 2008 The ORM Foundation: A UK not-for-profit organisation