Build a brief from evidence
Which evidence fits the decision and the available space?
Entering midway? Revisit Repair the survey headline for the preceding worked example, or start here and use the explanation below.
Start with a concrete question
Original fictional pilot: completion records, four interviews and timing observations describe different aspects of a product. Evidence bundles have explicit assumed word costs including context.
Try the initial inputs, then write a prediction before changing one setting. All calculations run locally on your CPU.
What do you expect?
Predict whether including every available observation proves that the product improves learning.
Change one thing. Inspect what happens.
- Inspect the completion and interview bundle; write one supported claim for each observation.
- Switch to timing. Identify which question you can no longer discuss from this bundle.
- Try all three under a 60-word budget and inspect the shortfall.
- Draft a recommendation, a limitation and the next measurement; ask a peer to review the reasoning.
Your settingsMechanism
Calculation belowEvidence
Compare outcomes
Compare the current results
Every bar starts at zero and uses the same numeric scale in this chart. The upper bound automatically adjusts to the largest current value (at least 1), so compare the numbers when changing inputs. Units and quantities come from each label; different kinds of quantity are not interchangeable. Displayed values are rounded to at most six significant digits.Follow the calculation
- Pilot: 18 of 30 users finished; 25 words including context; supports a statement about completion.
- Interview: 4 users described unclear labels; 20 words including context; supports a statement about reported confusion.
- None of these observations measures whether the product improves learning.
- 45 evidence words versus a 60-word budget. Titles above summarize fictional evidence; the word costs include assumed context.
The bundle fits. Draft a conclusion that stays within the selected observations and explicitly states what remains unknown.
Captures keep your inputs, prediction and observation. Results are recalculated from those inputs. Resetting inputs keeps your captures and challenge history.
Explain the mechanism
Build a brief from evidence
Original fictional pilot: completion records, four interviews and timing observations describe different aspects of a product. Evidence bundles have explicit assumed word costs including context.
Follow the mechanism
Evidence is relevant to a particular claim. Completion counts do not directly measure learning, and four interviews do not establish population prevalence.
The bundle calculation only accounts for space and distinct observations. It is not a score for persuasion, truth or writing quality.
A concise brief can identify an unresolved question instead of pretending the available evidence answers it.
Worked example
Pilot: 18 of 30 users finished; 25 words including context; supports a statement about completion.
Interview: 4 users described unclear labels; 20 words including context; supports a statement about reported confusion.
None of these observations measures whether the product improves learning.
45 evidence words versus a 60-word budget. Titles above summarize fictional evidence; the word costs include assumed context.
Calculation
Evidence words = sum of selected context-inclusive costs; over budget = max(0, evidence words − budget).
Try a controlled comparison
Inspect the completion and interview bundle; write one supported claim for each observation.
Switch to timing. Identify which question you can no longer discuss from this bundle.
Try all three under a 60-word budget and inspect the shortfall.
Draft a recommendation, a limitation and the next measurement; ask a peer to review the reasoning.
What this does not establish
The pilot and word costs are authored fixtures.
Recommendation prose and reasoning need human review; the lab only counts observable properties.
Try a fresh case
Three evidence excerpts require 18, 24 and 31 words including context. With a 60-word evidence budget, how many words must be removed?
This is a public practice check. Retries support learning; matching a number does not certify independent proficiency.
Take the investigation further
Choose any extension. These are project prompts for you to carry out; they are not automatically assessed.
School investigation
Write a 100-word proposal that names evidence and one unanswered question.
College investigation
Create a claim-to-source table and justify exclusions from an abstract.
Workplace investigation
Write a one-page decision brief separating observations, assumptions and recommendations.
Keep the evidence, choose your next step
Completion records your own decision that you have worked through this investigation. Practice checks and independent project evidence are separate.