How to make an information model?

Creating an information model is no simple task. It requires conceptual and critical thinking, creativity, and precision. It is an iterative and interactive process, where you constantly need to align with stakeholders, consult sources, test and improve models.

Creating an information model begins with understanding the context and purpose of the model. This requires a thorough analysis of the available information and a broad perspective to cover different viewpoints. It's important to remember that our perception of reality is always subjective and influenced by our perspective. Therefore, when modeling information, we need to consider different perspectives to get as complete a picture as possible.

Once the context and purpose are understood, the process of simplification begins. We identify general objects that are relevant to our purpose and ignore the rest. This is a crucial step in information modeling, as it determines which aspects of reality we include in our model and which we leave out. It is the modeler's task to make these choices and document the rationale behind them. This ensures transparency and makes the model easier to understand and use.

To help you create an information model, we have described 6 steps for creating an information model. We were inspired by the HIM - Handreiking Information Modeling. Steps 2 to 5 can be iteratively repeated until the information model has the desired quality. Remember that an information model is never really finished. It will always remain an imperfect approximation of reality. Let's take a very simple example to illustrate these steps. Suppose you want to create an information model for a library. This is what you could do:

Step 1: Determine scope

Determine the scope and level of detail of the model. This step is extremely important and it is recommended to create a scope document. You and your client must agree on the content of this scope document. In this scope document, you will want to describe the usage purpose that the information model must cover. In addition, the context in which the model focuses must also be described. Agreements can also be included about the level of detail, the time in which it must be delivered, and who the stakeholders are. You want to create a model that shows which books are in the library, who has borrowed them, and when they should return. You choose to use MIM as a modeling language, as this is a standard for information models in the Netherlands.

Step 2: Collect information needs

Collect and analyze the information needs of the stakeholders. You do this by having a conversation. This can be informal or in the form of interviews, working groups, or by sending out a questionnaire, for example. Scenarios (Use Cases) that the model must cover are described. New information needs can possibly be discovered by applying scenario analyses in step 5. In the case of the library, the stakeholders include the library staff, the members, the suppliers, and the regulators. They have different information needs, such as:

1. The library staff want to know which books are available, who has borrowed them, and when they should return.
2. The members want to know which books they can borrow, how long they can keep them, and what fines they have to pay if the books are returned late.
3. The suppliers want to know which books have been ordered, when they should be delivered, and how much they cost.
4. The regulators want to know how many books are in the library, how often they are lent out, and how much income is generated.

Step 3: Identify object types

Identify and define the concepts/object types used in the model. It doesn't matter what medium you use here. Pen and paper also suffice. The main object types you want to model are: o Book: an object that contains information about a certain subject or story. A book has properties such as title, author, genre, ISBN, price, and status. A book can have relationships with other books, such as being part of a series or having a sequel. o Loan: an object that contains information about lending a book to a member. A loan has properties such as start date, end date, fine, and extension. A loan has relationships with a book and a member, such as lending a book to a member. o Member: an object that contains information about a person who is a member of the library. A member has properties such as name, address, phone number, email address, and membership number. A member can have relationships with other members, such as being family or friends.

Step 4: Design information model

Design and document the model and apply MIM. You create one or more diagrams that show the object types and their relationships. You use a modeling environment such as Enterprise Architect. Here you enter additional information, the metadata. MIM prescribes a number of mandatory and optional metadata. For example, each object type, each attribute type (property), and each relationship has a definition according to MIM. For our example of the library, this might look like this:

Book:

• Title: the name of the book Author: the name of the person who wrote the book
• Genre: the category to which the book belongs, such as fiction, non-fiction, thriller, romance, etc.
• SBN: the international standard book number that identifies the book
• Price: the amount the book costs
• Status: the availability of the book, such as available, borrowed, reserved, etc.
• Is part of: the relationship with another book of which this book is part, for example a series or a trilogy
• Has sequel: the relationship with another book that is the sequel to this book

Loan:

• Start date: the date the book was borrowed
• End date: the date the book should be returned
• Fine: the amount to be paid if the book is returned late
• Extension: the number of times the loan has been extended
• Borrows: the relationship with a book that is borrowed
• By: the relationship with a member who borrows the book

Member:

• Name: the name of the person who is a member of the library
• Address: the address where the person lives
• Phone number: the phone number where the person can be reached
• Email address: the email address where the person can be reached
• Membership number: the number that identifies the member
• Is family of: the relationship with another member who is family of this member
• Is friend of: the relationship with another member who is friend of this member

Step 5: Model Validation

Validate and verify the model using various techniques. You ask for feedback from stakeholders to see if they are satisfied with the model and if they have suggestions for improvement. This can be done, for example, by scheduling a working session, or by discussing new pieces of the information model during a periodic sprint review session. You also test whether the model works as expected by, for example, simulating scenarios with test data or creating prototypes. If it turns out that certain scenarios do not yet fit within the information model, we go back to step 2.

Step 6: Publication and Management

Once the information model has been developed to everyone's satisfaction, the model can be established. Publish and maintain the model according to previously agreed standards and procedures. Use the Management and Development Model for Open Standards (BOMOS) for this. You make the information model accessible to users and ensure good documentation and communication. You also keep the model up-to-date by processing changes in the information or context.

In this blog, you have learned how to create an information model. You have seen the steps you need to follow to create a good model and how to apply them to a simple example. In the next blog, we will discuss how information modeling is applied within the education domain. So keep reading!