CORD an Object Model
supporting Statistical Summary Information for Management Decision Making
PAUL ANTHONY GOLDER
Doctor of Philosophy
ASTON UNIVERSITY
October 1997
This copy of the thesis has been supplied on condition that anyone who consults it is understood to recognise that its copyright rests with its author and that no quotation from the thesis and no information derived from it may be published without proper acknowledgement.
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Summary
Aston University
CORD an Object Model
supporting Statistical Summary Information for Management Decision Making
PAUL ANTHONY GOLDER
Doctor of Philosophy
1997
Information systems have developed to the stage that there is plenty of data available in most organisations but there are still major problems in turning that data into information for management decision making. This thesis argues that the link between decision support information and transaction processing data should be through a common object model which reflects the real world of the organisation and encompasses the artefacts of the information system. The CORD (Collections, Objects, Roles and Domains) model is developed which is richer in appropriate modelling abstractions than current Object Models. A flexible Object Prototyping tool based on a Semantic Data Storage Manager has been developed which enables a variety of models to be stored and experimented with. A statistical summary table model COST (Collections of Objects Statistical Table) has been developed within CORD and is shown to be adequate to meet the modelling needs of Decision Support and Executive Information Systems. The COST model is supported by an statistical table creator and editor COSTed which is also built on top of the Object Prototyper and uses the CORD model to manage its metadata. Keywords
Object modelling; Statistical Summary Tables; Statistical Metadata; Management Information; Decision Support; Object Database Management.
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Acknowledgements
My thanks to Vivienne for inspiration, encouragement,
support and a lot of checking.
Copyright
The author acknowledges the rights of the following companies to the products referred to in the text
Microsoft Corporation : Visual Basic, MS Access, Excel
Oracle Corporation : Oracle, SQL*Forms
Seagate Software Information Management Group : Crystal Reports
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List of Contents
CORD an Object Model
supporting Statistical Summary Information
for Management Decision Making
Paul Anthony Golder
Title Page (1)
Summary (2)
Acknowledgements (3)
List of Contents (4)
List of Figures (5)
List of Tables (9)
Chapter 1 Information from Data (10)
Section A Conceptual Modelling and the CORD model (24)
Chapter 2 The Nature of Data (28)
Chapter 3 Objects and Classes (44)
Chapter 4 Modelling the Dynamics of Objects (58)
Chapter 5 Entities and Roles (68)
Chapter 6 Relationships and other Associations (91)
Chapter 7 The CORD Model (108)
Chapter 8 The Object Prototyper (130)
Section B From Data to Management Information (150)
Chapter 9 Modelling the information system (155)
Chapter 10 Statistical Summaries (167)
Chapter 11 The Collections of Objects Summary Table Model (196)
Chapter 12 Structural Summaries (214)
Chapter 13 The Presentation Model (226)
Chapter 14 Implementing the COST Models (241)
Chapter 15 Conclusions (261)
References (274)
Appendix 1 CORD model (280)
Appendix 2 COST model (286)
Appendix 3 Test models (287)
Appendix 4 The initial triples (292)
Appendix 5 Examples of COST models (294)
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List of Figures Continued
Figure 1.1The various domains implicit in the research (16)
Figure 1.2Matching model to problem domain (21)
Figure 2.1Levels of data abstraction (30)
Figure 2.2 A record and three sentences derived from it (33)
Figure 2.3Dimensions and scales of measurement (35)
Figure 2.4Approximate relationships between data forms (38)
Figure 2.5 A conventional E-R model (39)
Figure 2.6An instantiation of figure 2.5 (40)
Figure 2.7Representing Attributes in OOA (41)
Figure 2.8Attributes and an instance in OMT (42)
Figure 3.1Different levels of abstraction (44)
Figure 3.2Nested domains of discourse (45)
Figure 3.3 A variety of relationships (47)
Figure 3.4Two generalisation constructs (49)
Figure 3.5An aggregation hierarchy (49)
Figure 3.6Representing Classes and Objects in OOA (53)
Figure 3.7OMT notation for classes and objects (54)
Figure 3.8 A class and object with attribute values (54)
Figure 3.9Links and associations (55)
Figure 3.10Generalisation / specialisation structures (55)
Figure 3.11Whole part structures (56)
Figure 4.1Actions, Events and Processes (58)
Figure 4.2State diagram (after Rumbaugh) (63)
Figure 4.3Library member model (after Jackson) (65)
Figure 4.4Examples of Entity Life Histories (65)
Figure 5.1Subtypes and Roles (71)
Figure 5.2An ORD - Union Membership as a Role (72)
Figure 5.3Not an ORD - Union Membership in a Closed Shop (73)
Figure 5.4 A sub role (73)
Figure 5.5Concurrent Roles (74)
Figure 5.6Mutually exclusive roles (74)
Figure 5.7 A sequence of roles (75)
Figure 5.8The missing roles (76)
Figure 5.9Roles replacing transitions (76)
Figure 5.10More accurate representation of advanced first aiders (77)
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List of Figures Continued
Figure 5.11An E-R model of a relationship (77)
Figure 5.12The Object Role diagram for Figure 5.11 (78)
Figure 5.13Cardinality of Roles (79)
Figure 5.14Required Occurrence of Roles (80)
Figure 5.15 A complex Entity Life History (81)
Figure 5.16Three simpler ELHs (81)
Figure 5.17States and roles (82)
Figure 5.18Specialisations of natural kinds and roles (83)
Figure 5.19Figure 5.1 reprised (84)
Figure 5.20 A specialisation of Research Project (85)
Figure 5.21Two different ELHs completely defined (85)
Figure 5.22Only the different activity is defined (86)
Figure 5.23Life Histories and Roles (Figure 5.16 reprised) (87)
Figure 6.1Cardinality of relationships with role names (92)
Figure 6.2 A required relationship (93)
Figure 6.3An alternative representation (93)
Figure 6.4Several different relationships (93)
Figure 6.5Binary relationship modelling (94)
Figure 6.6Instance connections in OOA (95)
Figure 6.7Links and associations in OMT (95)
Figure 6.8Association showing Roles (96)
Figure 6.9 A Part_ Of association (OMT) (96)
Figure 6.10Whole Part Structures (97)
Figure 6.11Conceptual modelling of the implementation (99)
Figure 6.12E-R model with a classification entity (99)
Figure 6.13Description of a class (100)
Figure 6.14An instance of the class in Figure 6.13 (101)
Figure 6.15Two different DoDs (101)
Figure 6.16References and domains (105)
Figure 7.1An Object Class (112)
Figure 7.2Specialisations (112)
Figure 7.3Role (118)
Figure 7.4Distinct class model (123)
Figure 7.5Mule model (124)
Figure 7.6Synchronisation model (124)
Figure 7.7Partnership model (124)
Figure 7.8Main elements and relationships in the CORD model (128)
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List of Figures Continued
Figure 8.1Main Screen Menu (142)
Figure 8.2The Loader Screen (143)
Figure 8.3The OQL form (144)
Figure 8.4The Object Tree (145)
Figure 8.5The Browser (146)
Figure 8.6Print form (146)
Figure 9.1Nested levels of modelling (155)
Figure 9.2 A screen form (160)
Figure 9.3Typical MIS report (161)
