Test a cause hypothesis using the work record
See this course’s project requirements
Collect and revise all six lesson outputs into a fictional process-improvement plan. Show how the process works now, starting measurements, a possible cause of the problem, a Plan-Do-Check-Act test, a review of the results, and checks to keep the improvement working. Label it as fictional practice.
Keep your working files in your own notebook or software. Save a private description, checklist, and work link in My Proof.
What to include
- Map the bounded current process with decisions and rework.
- Calculate baseline capacity, elapsed time and first-pass accuracy.
- Document a cause hypothesis and one targeted improvement.
- Plan, perform and evaluate the supplied ten-request paper PDCA test against predefined measures; preserve the row-level record and the separate unknown-location exception test.
- Assemble a control plan with ownership, triggers and a response to a failing sample.
Review and revise
Use these criteria to check your work and choose what to improve.
- Accuracy: amounts, classifications and decisions agree with the supplied evidence and stated assumptions.
- Reasoning: each important choice names the rule, observation or comparison that supports it.
- Responsible scope: the packet protects information, respects authority limits and routes unresolved concerns appropriately.
- Usability: a new reader can follow the ordered lesson outputs, identify ownership and see what is complete or still uncertain.
Want more background?
The idea in everyday life
An error category tells you what went wrong, not necessarily why it happened. Cause investigation looks at inputs, instructions, handoffs and checks before blaming individuals. A small set of records can guide a test, but it rarely proves a single universal cause. Choose an improvement that addresses a supported mechanism and leaves other explanations open.
A plausible cause becomes useful when evidence connects it to the failure.
One step at a time.
Use the sample or information you have permission to use. Keep your work as you go. You can pause between steps.
- 1
Create a defect check sheet listing the three corrections by observable type. Keep missing location and wrong time separate, and confirm that the counts sum to the three corrected outputs.
- 2
Compare the input format for each supplied case. Write a cause hypothesis linking a missing structured field to the missing-location defect, then state what the current sample cannot establish.
- 3
List one alternative explanation, such as unclear instructions or an outdated reference, and identify what additional observation would help distinguish it from the chosen hypothesis.
- 4
Select one small change for a pilot and explain why it matches the evidence. Preserve the wrong-time issue in the investigation notes instead of pretending the chosen change addresses every defect.
See how it works.
Fictional practice: Fern’s three baseline corrections include two missing-location confirmations and one wrong-time confirmation. The two missing-location requests used a blank free-text intake format; the seven first-pass-correct requests used a structured form. The wrong-time request used the structured form but copied an old time from a previous event. This pattern suggests testing a required location field and checking the approved event record during entry. It does not prove that every free-text request fails or that one employee caused the problem. For the first pilot, Fern selects only the required-location intake field so its effect can be studied with fewer simultaneous changes.
Did you cover these?
- Defect counts are two missing locations and one wrong time.
- The hypothesis connects an input feature to a specific defect.
- The wrong-time cause remains separately unresolved.
What to finish
A defect summary, evidence-linked cause hypothesis and one proposed pilot change.
Watch for this
Treating correlation in a small sample as proof, or blaming a person without evidence.
How can I tell I understand it?
You can demonstrate all three checks and explain the evidence behind your choices without consulting the worked example.
Quick knowledge check
Answer all 3 questions. Get at least 2 right and the lesson completes automatically.
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Answer all 3 questions above and get at least 2 right. You can review the explanations and try again.
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Source & access notes · checked 2026-09-10
Opened and read check sheets, cause-and-effect tools and comparison with historical process performance. Course thresholds are fictional action triggers, not statistically calculated control limits.
Access: Free page readable without an account; optional further study only.
Reuse: Reference for original Life Starter instruction. Free access does not grant unrestricted reuse; no source exercises, logos or syllabi are copied. Check the source license before redistributing its material.
Source & access notes · checked 2026-09-10
Opened the public article and read its four-step procedure and small-scale testing description. Optional commercial training links appear on the page; none are required. No ASQ certification is implied.
Access: Public explanation is free; linked training, books or certification may require payment and are optional.
Reuse: Reference for original Life Starter instruction. Free access does not grant unrestricted reuse; no source exercises, logos or syllabi are copied. Check the source license before redistributing its material.
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