Case Studies and Anti-Patterns · AI Purple: the course

All courses / AI Purple / Module 7 / Chapter 26

Learning objectives

After the lesson the participant can:

Classify a described failure as one of the eight anti-patterns and name the stage it breaks.
Explain the mechanism and the early signs of each anti-pattern and the control that changes the outcome.
Compare the four kinds of case material and say what each can and cannot support.
Review a loop against the seven steps of the loop review and draft an anti-pattern record for one pattern found.

Key concepts

Purple theatre: A session with no re-test: findings carry a change identifier and no re-test log, and the closure date equals the merge date. It breaks P5 Verify, and the control is the closure rule with implemented-unverified as a state.
Grading its own homework: A check in which tester and tested share a model, training data, prompts or a vendor, so that their errors correlate. The control is the independence statement, held-out scenarios and seeded gaps.
Coverage by assertion and the green dashboard: A coverage figure without a date, or a map coloured by the existence of a rule, and a dashboard that counts runs. The controls are a coverage record with last test, result and expiry, and cells that carry age.
The emulation that became an incident: An emulation whose blast radius includes what the estate does in response, for example a scope silent on calendars and dependencies. The controls are safety classes, scope as code and a stop path outside the runner.
Anti-pattern record: An AP record in the loop repository with the pattern, signs, evidence, owner, control, decision and a re-test date, so that a loop review can find each pattern and follow its remedy.

Interactive exercises

Do them here and get feedback at once. Choose a card and then where it belongs, or drag it.

Interactive exercise 1 · Sort

Where each anti-pattern breaks the loop

Sort each anti-pattern by the stage of the loop that the chapter's table says it breaks.

Interactive exercise 2 · Scenario

A sample of closed findings

Apply the first step of the chapter's loop review to the result of a sample.

Teaching plan

15 min	The teacher presents the four public cases, describing only what the sources report, and the four kinds of material: public, composite, illustrative and the book's own conclusions.
20 min	Matching task: eight short case descriptions are matched to the eight anti-patterns, with the stage broken and one early sign for each.
35 min	Exercise: run the loop review on the participant's own loop or on a supplied case file and write one anti-pattern record.
10 min	Groups read the table of where each pattern is most likely by usage mode and explain why the delegation profile is the first document to read in a review.
10 min	Plenary: which pattern is each organisation closest to, and what is the re-test date for its remedy.

Discussion

The chapter says loops fail where a step was reasonable and a question was not asked. Take one anti-pattern: which reasonable step, and which unasked question?
Nordvik Region's anti-patterns come from buying a loop and Hansa Mutual's from running one. Which family does your organisation belong to, and does it also carry the other?
A draft pack at Nordvik Region said nine of nine priority techniques were mapped to a detection. What made that sentence easy to write, and what made it wrong?

Written exercise

Exercise · 35 minutes

A loop review for the eight patterns

Run the chapter's loop review on your own organisation, or on the records of Hansa Mutual and Nordvik Region as the book gives them. Draw a sample of findings closed in the last two quarters and ask for each re-test log and evidence manifest. For five claims on the coverage map, ask for the last test, the result and the expiry. List every agent and tool that plans, runs, drafts or checks, with vendor and model family. For each class of scenario in production, ask who holds the stop and how long a drill took. Inventory where findings live. Read the contracts for a testing right. For each of the eight patterns write found, not found or not testable, and write an anti-pattern record for one pattern found.

Deliverable: A review sheet with an entry per pattern and the evidence read, plus one anti-pattern record with owner, control and re-test date.

Your work

Self-test

Choose an answer to see whether it is right, or open the answer below each question.

Which early sign points to purple theatre?
Show the answer
A. A closure date that equals the merge date, and findings with no re-test log.
Purple theatre is a session with no re-test. Its early signs are findings that carry a change identifier and no re-test log, and a closure date equal to the merge date. The other signs belong to patterns 2, 7 and 8.
Which control answers the anti-pattern of overfitted detections?
Show the answer
C. Detection from a behaviour description, variants, a negative control and the held-out gap.
Overfitting arises when the test becomes the target. The control is to draft from behaviour and not from a log line, include variants and a negative control in every regression case, and watch the gap on a held-out share.
What does the chapter conclude from its cases about AI and the loop?
Show the answer
D. That no case shows AI made the loop unnecessary or unsafe in itself.
The chapter states that no case shows AI made the loop unnecessary or unsafe in itself. Loops fail where a step was reasonable and a question was not asked, and the controls are few and the book's own.