Computing case analysis: evaluate a proposed system
Đã giới thiệu| English | Ý nghĩa |
|---|---|
| throughput/ˈθruːpʊt/ | tốc độ truyền tải |
| acceptance test/əkˈseptəns test/ | kiểm tra chấp nhận |
What would explain this observation?
- A proposed school booking system looks efficient, but its recommendation depends on users, constraints and evidence. A plausible technical term alone is not a justified decision.
Build the model
- A case study places computational choices within a stated scenario.
- Identify stakeholders, requirements, available evidence and constraints before recommending an architecture or algorithm.
- Distinguish a scenario fact from an assumption and a prediction.
- Trade-offs can involve performance, reliability, accessibility, privacy, maintenance and cost.
- throughput 吞吐量: Completed work per unit time under a stated workload.
- acceptance test 验收测试: A test of whether a specified user requirement is met.
Which statement best supports a technical recommendation?
Độ khó 1/5 · 100 xu + một phần thưởng nhỏ cho lần hoàn thành đầu tiên trong ngày
A recommendation earns trust by naming the mechanism that meets a scenario requirement and a measurable test that would show it working. A fashionable name is not evidence, and one throughput number cannot certify latency, reliability or scale.
Match each technical term to its precise meaning.
Độ khó 2/5 · 140 xu + một phần thưởng nhỏ cho lần hoàn thành đầu tiên trong ngày
Use the definitions to distinguish related quantities and processes.
Choose evidence that can test it
- A recommendation should connect a requirement to a mechanism and an observable test.
- For example, a concurrency problem requires a strategy that prevents conflicting updates, plus tests demonstrating the invariant.
- A claim about faster response requires comparable workload measurements rather than only a complexity label.
- Evaluate alternatives under the same stated conditions.
In the lab: Use an original school-approved scenario and synthetic data. Build a matrix of claim, supporting scenario evidence, technical explanation, limitation and acceptance test. Mark missing facts explicitly and show how the recommendation would change if an assumption failed. This prepares case-based reasoning without reproducing an unavailable IB assessment case study or inventing its examination rubric.
Which two habits make the investigation or model in this case more defensible?
Độ khó 2/5 · 140 xu + một phần thưởng nhỏ cho lần hoàn thành đầu tiên trong ngày
Stating the conditions and assumptions lets others repeat the work exactly, and recording the supporting evidence lets them check the conclusion. Hiding disagreeing results removes the evidence that could challenge a wrong conclusion, and one measurement can never establish a wider claim.
Work from known quantities
- Known: a fictional prototype processes 120 successful requests during a 30-second observation.
- Throughput is 120/30=4 successful requests/s.
- A second prototype processes 150 in 30 seconds, or 5/s.
- The second has 25% greater recorded throughput, but no conclusion about latency, failure rate or performance under a larger workload follows without those measurements.
Your turn: A fictional system successfully processes 210 requests in 30 s. Calculate throughput.
A fictional system successfully processes 210 requests in 30 s. Calculate throughput.
Độ khó 2/5 · 140 xu + một phần thưởng nhỏ cho lần hoàn thành đầu tiên trong ngày
The result is 7 requests/s. Known: 210 successful requests in 30 s. Use throughput = requests / time. Throughput = 210/30 = 7 requests per second. This says nothing about response time or failure rate without those measurements.
Check the conclusion and its limits
- Throughput is not response time.
- A strong recommendation states the conditions in which it is expected to work and the evidence that could disconfirm it.
- Current official CS case-study requirements must be checked against the applicable assessment version.
Not true: Higher observed throughput automatically proves lower response time for every request. Throughput counts completions per second; response time is how long each request takes. A system can batch work for high throughput while individual requests wait - so one metric cannot prove the other.
- A case study places computational choices within a stated scenario.
- A recommendation should connect a requirement to a mechanism and an observable test.
- Watch for: throughput is not response time.
Throughput counts completions per second; response time is how long each request takes.
Độ khó 1/5 · 100 xu + một phần thưởng nhỏ cho lần hoàn thành đầu tiên trong ngày
True. Throughput counts completions per second; response time is how long each request takes. A system can batch work for high throughput while individual requests wait - so one metric cannot prove the other.
Completed work per unit time under a stated workload: write the technical term.
Độ khó 1/5 · 100 xu + một phần thưởng nhỏ cho lần hoàn thành đầu tiên trong ngày
throughput means Completed work per unit time under a stated workload.