2) Determination of Requirements Flashcards
On completion of this unit, you will be able to define a system context and explain how it can be determined, list the sources available for the determination of requirements, explain the different investigative techniques available for requirements engineers and the circumstances for which each technique is preferable, describe the transformational effects that can occur during requirements engineering and how the requirements engineer can try to compensate for them.
Please name and define the activities for the elicitation of requirements.
1) Determine system context
An analysis of which stakeholders or systems are directly dependent on the system in development so that they have an idea on the sources of requirements.
2) Identify sources of requirements
Typical sources of requirements:
* Stakeholders
* Documents (laws & policies)
* Other systems (legacy or competing systems)
3) Select appropriate determination techniques
Depending on the sources of requirements, project situation, and the nature of the requirements, an appropriate selection of elicitation techniques must be selected.
4) Elicit requirements using the techniques
Requirements are elicited from the sources using the selected techniques at the level of detail required for the current situation.
Please define the system context.
The system context is the relevant part of the system environment that must be analysed to define and understand requirements.
The system context is the relevant part of the system environment that must be analyzed to define and understood requirements. Includes stakeholders and systems that interact directly with the developing systems.
Explain the process to selecting stakeholders for requirements elicitation.
Searching for stakeholders normally begins with the planning of a project and nominating those directly involved. The stakeholders are asked whe else is a relevant bearer of knowledge, decision maker in the project area, or interested supported.
The circle can grow very quickly through the snowball system, so it may be necessary to reduce. Management can refuse to involve individuals because they lack the necessary skills or resources. Those with outdated knowledge or who are not prepared to communicate sufficiently will not be involved.
Stakeholders should be chosen carefully as forgotten stakeholders can lead to unnecessary and expensive changes.
Please define the different stakeholder archetypes.
Doers
* High influence and motivation
* They should be involved as much as possible because they have the power to enforce decisions and the will to drive the project foward.
Powerful
* High influence and low motivation
* Enough effort should be invested to satisfy these and maintain good contact, but should not be bored with too much information and details.
Seismographs and preachers
* Low influence and high motivation
* These stakeholders should be informed about developments in the project and good communication should be maintained, they can quickly alert the requirements engineer if there are problems.They can often provide important information about the project and have no problem exciting others with their enthusiasm.
Observers
* Low influence and low motivation
* They should not be forgotten, and isn’t necessary to invest too much effort in their care. It is sufficient to make the relevant information available online and provide access.
Kindly define a stakeholder.
A stakeholder is someone who influences the formulation of requirements directly or indirectly.
The investigation techniques can be grouped into four categories. Please name them.
- Interviewing techniques
- Creative techniques
- Document-centered techniques
- Observation techniques
Please make sure to go over the table for the investigation techniques.
Please state which methods are suitable for finding requirements that are unknown to both the customer and supplier.
- Market research
- Design thinking
- Role playing
- System modeling
Make sure to revise the table!
Please name the three representational transformations than can take place during elicitation of requirements.
1) Deletion
2) Generalization
3) Distortion
How does a perception transformation takes place when eliciting requirements?
Every requirements engineer has to describe a real or yet-to-be developed system based on the client statements or stakeholder interviews. The described reality is changed by the personal perception of the interviewees (humans can only perceive a part of reality) and is thus subject to a transformation of perception. The personal knowledge of the respondent, their social conditioning, and their prebious knowledge will ensure that the perception is interpreted differently.
How does representational transformations occur?
Representational transformations occur because a transformation takes place as soon as a person expresses this image in language.
It also takes place when the respondent formulate their requirements. The interviewee asumes a basic knowledge of the interlocutor, meaning of the terms and their context, the absence of this knowledge will lead to further misinterpretation on the part of the listener.
Can transformations be reversed?
For perceptional transformations, this is impossible.
However, the wrong impression of the engineer can be corrected by asking several people about the same issue. Representational transformations can be resolved if the engineer adheres to the rules.
What are the challenges of linguistic representation?
Deep structure & Surface Structure
Linguists asume that humans form a complete linguistic representation (deep structure) in their minds from their preception. This is the original image before it is translated into language.
When the communicate, they make a series of choices regarding the shape of the information to be articulated, forming the associated surface structure, the transformed version of the original.
There may be missing or misinterpreted parts. The goal of requirements analysis is derived from this assumption. In order to obtain a complete image of the stakeholder’s perception, the engineer must identify the corresponding deep structure from the surface structure.
When does representational transformation occur?
Representational transformation occur because transformation takes place as soon as this image is expressed in language.
Define Deletion:
Deletion occurs when we delete parts of the information that we subconsiously assume to be known by the recipient of the information. The process of deletion condenses the full amount of information that is transmitted to us into smaller amounts we can handle.
Define Generalization:
Generalization occurs when a unique experience is transferred to a similar situation and thus accepted as valid.
Generalization is useful in the context of system analysis. It is important to group the circumstances appropriately.
