Know and understand evaluating a solution including the efficiency of the solution, the ease of use of the solution, and the appropriateness of the solution

Topic 7 – The Systems Life Cycle

Evaluating a Solution

During the Evaluation stage of the systems life cycle you assess how well a proposed solution meets the user’s needs. The assessment focuses on three key aspects:

1. Efficiency of the solution
2. Ease of use (usability)
3. Appropriateness to the problem context

1. Efficiency of the Solution

Efficiency measures how well the system performs its required tasks with minimal resource consumption. Typical metrics include:

• Response time – time taken to complete a user request.
• Throughput – number of transactions processed per unit time.
• Resource utilisation – CPU, memory, and storage usage.
• Cost per transaction – financial cost divided by number of transactions.

Example calculation of cost per transaction:

\$ \text{Cost per transaction} = \frac{\text{Total cost of system}}{\text{Number of transactions}} \$

2. Ease of Use (Usability)

Usability evaluates how easily users can learn, operate, and achieve their goals with the system. Key indicators are:

• Learnability – time taken for a new user to perform basic tasks.
• Efficiency – speed of task completion for experienced users.
• Memorability – ability to recall how to use the system after a period of non-use.
• Error rate – frequency of user errors and difficulty in recovering from them.
• – user satisfaction ratings collected via surveys.

3. Appropriateness of the Solution

Appropriateness considers whether the solution fits the problem context and stakeholder expectations. Factors include:

• Alignment with business goals and user requirements.
• Compliance with legal, regulatory, and security standards.
• Scalability and future‑proofing.
• Compatibility with existing systems and infrastructure.
• Maintainability and supportability.

Evaluation Rubric

Sample Assessment Questions

1. Identify two efficiency metrics that would be relevant for a web‑based e‑commerce platform and explain how you would measure them.
2. Describe a usability test you would conduct to evaluate the learnability of a new software application.
3. List three factors that determine the appropriateness of a solution for a small non‑profit organization.
4. Using the rubric above, evaluate the following scenario: A mobile app that processes 500 transactions per hour, has a response time of 3 s, and an error rate of 4%. Provide a score for each criterion.

Suggested Diagram