Week 9 Tutorial: Transitioning to Offline Environments

Plan the digital-to-physical handshake: public venues, transport, accessible exits, confirmation and an agreed approach to the bill.

6 May 2027

Inputs#

Bring the Threat model, Match probability model and Alex’s fixed Friday 5–7 pm, bus and $20 total constraints. Retain the earlier candidate and invitation versions, unresolved findings and closure reason. Work solo or review with a partner; both modes are accepted.

Open the ten-file offline workbook. It recalculates the unchanged Week 5 Library plan (100 minutes, $14) and constructs the actual Week 8 review snapshot. Week 9’s new Atrium proposal is a separate 90-minute, $14 fixture. Do not merge the two durations or infer acceptance from review clearance. Venue observations, prices, events and probabilities are authored; no actual venue search, booking or payment is required.

Finish with The itinerary mistakes itself for an agreement: the interactive quiz. Six new cases include venue cards, a contingency diagram and confirmation branches. Apply the week’s constraints, probability and agreement rules, then submit all six responses to unlock the score and worked explanations. The quiz is practice and carries no course marks.

Follow the 60-minute lecture selection and independent-work plan. Complete the preparation and open the workbook before Thursday. The four blocks below are the entire 90-minute tutorial; use existing lecture or study working for review and refinement. Remaining pack material belongs to the week’s independent study allocation.

90-minute tutorial#

1. 20 minutes — filter venues. Spend eight minutes tracing the three primary cards, seven listing every rejection and five reviewing the checked Annex alternative. Use public/private setting, opening times, route access, noise, lighting, transport and exits. Apply hard checks before preference scores. Explain why delaying the Gallery departure repairs its opening mismatch but worsens its late return. Save one route timeline and the rejection table.
2. 20 minutes — specify the handshake. Spend six minutes drafting a minimal optional invitation, six comparing cover-both and split-drinks costs, and eight replaying version-specific confirmations and cancellation. Record a confirmation point before departure and a cancel branch. Use the report’s supplied events, not another student’s messages. Revise the cost arrangement and show both confirmations being cleared. A confirmation can be withdrawn; an earlier one cannot cover changed terms.
3. 30 minutes — enumerate contingencies. Spend ten minutes listing late/on-time × open/closed, ten calculating means and strict exceedance, and ten checking the model’s assumptions. Verify expected $14.60, 96 minutes and 2.5% beyond 110 minutes. Check against dateLogistics. Explain why no supplied row exceeds Alex’s 120-minute hard window or $20 budget even though one misses the 110-minute working target.
4. 20 minutes — dependence review and quiz. Use ten minutes to review your prepared dependence calculation: four checking the conditional probabilities, three checking marginals and means, and three checking the changed tail and your mutation/restoration evidence. Set closure given lateness to 0.4 and closure given on-time to 0. Keep marginal closure at 0.1; show that the late-and-closed tail rises to 10% although both means stay unchanged. Retain the restored passing result. Use the final ten minutes for the six-case quiz: about eight minutes to respond and two to review the explanations after all cases are answered.

Worked checkpoints#

The closure branch assumes a usable alternative adds $6 and ten minutes. This assumption does not authorise an automatic venue switch. A changed place, time or cost needs fresh agreement; a failed hard constraint requires revision or cancellation. The numerical fixture omits further delays and a second closure.

Protocol checks#

Start from a genuine unheld replied Week 8 record; held, pending or closed records cannot start a new proposal. Record the proposal and two explicit actor/version confirmations. Assert phases proposed → proposed → confirmed. One actor’s event is insufficient.

After a split-drinks revision, assert zero confirmations and a new version with Alex’s proposed total $8. A confirmation for the previous version must fail. After cancellation, assert that the complete snapshot remains unchanged even if a later confirmation arrives. A fresh threat-review update clears the agreement; before the confirmation deadline, an eventual clear update returns to draft rather than restoring acceptance.

At the 16:30 confirmation point, an unfinished plan expires. A final confirmation at 16:29 can complete it; at 16:30 it is late. New event IDs must be chronological, exact serialized duplicates are no-ops, and conflicting IDs fail. The workbook records local states and performs no messaging, booking or payment.

Make one check fail#

Predict the original >110-minute tail as the literal value 0.025. Temporarily change the strict > comparison to ≥, asserting the edit matched. The test must fail because the 110-minute row is now incorrectly counted. Restore it and verify the passing result.

Alternatively, change the two-confirmation condition to accept one actor; the literal phase trace must fail. Preserve the failed assertion and restored output. Searching the source for the word “confirmed” would not check the behaviour.

If you finish early, derive the joint late/closed bounds 0 to 0.10 from the fixed marginals. Or deliberately change the base duration to 100 minutes: the mean becomes 106 minutes and the >110-minute tail becomes 25%. Label that as a changed scenario, not an unannounced repair to the original fixture.

Deliverable: Offline handover plan#

Save the venue decisions and route timeline, minimal-information invitation, versioned cost arrangement, confirmation/cancel traces, original and dependent contingency tables, and one mutation/restoration result. State the independence and fallback assumptions. Record why a failed hard constraint cannot be compensated by good lighting. These artefacts form one Offline handover plan, not a new essay or extra assessment.

Week 10 consumes the currently confirmed plan and its explicit cost agreement when modelling conversation and the bill. Export the version and unresolved conditions as well. Confirmation does not prove arrival or continuing agreement; a cancelled, expired or held plan cannot be exported as accepted.

Interactive quiz · 6 cases · about 8 minutes + 2 to review

The itinerary mistakes itself for an agreement

Six planning tickets. The backup venue has already invited itself.

Make a decision in every case, then select Reveal answers. You can change any response before submitting. Scores and explanations stay hidden until the whole quiz is answered.

All venues, prices, events and probabilities are authored fixtures. Cases 3–5 use one new contingency model and stated changes to it; the other cases are separate planning records. Alex’s Friday 5–7 pm, bus and $20 constraints remain fixed. Practice only: no course marks. Responses stay on this page; reloading starts a fresh attempt.

The cases are readable without JavaScript. Enable JavaScript to navigate, submit your responses and unlock the explanations.

Case 01 / 06The best lighting cannot find the exit

Filter hard constraints before preference scores

Three new fictional venue cards have the observations below. All required checks not mentioned in a row pass, including opening times, the specified step-free route and bus travel. An unknown exit means independent departure has not been verified. Scores use the supplied preference weights, not new facts about Alex.

Authored venue checks · higher preference scores rank only eligible venues

Venue	Hard observations	Score
Nook	Public; exit unknown	19
Den	Private; exit checked	20
Arcade	All pass; home 19:00; total $20	12

Which selection follows the Week 9 filter?

AChoose Nook after subtracting a small penalty for its unknown exit.BChoose Den because its score of 20 compensates for the private setting.COnly Arcade is eligible. The exact time and budget limits pass; the other two remain excluded.DReject all three: arriving home at 19:00 or spending exactly $20 violates a hard limit.

Case 02 / 06The cheaper bill loses two signatures

Keep cost arithmetic and versioned agreement separate

A separate feasible plan v1 has two $7.50 drinks and $3 of Alex’s round-trip transport. Both actors confirmed Alex covering both drinks. Before the confirmation point, a recorded revision creates v2 with split-drinks: “Could we each cover our own drink? Either of us can cancel.” No actor has confirmed v2. The counterpart’s transport cost is unknown.

What costs and agreement state should the revised record show?

AAlex proposes $10.50; counterpart proposes $7.50 for a drink, with transport unknown. v2 has zero confirmations and needs both actors again.BAlex proposes $10.50 and counterpart $7.50. Keep both old confirmations because Alex’s bill became cheaper.CEach pays $9, splitting Alex’s transport too. The arithmetic itself confirms the revised arrangement.DAlex pays $10.50; counterpart’s complete cost is exactly $7.50 because no transport price was supplied.

Case 03 / 06The 110-minute row tries to join the tail

Enumerate joint outcomes with strict exceedance

A new contingency fixture starts at 85 minutes and $18. Lateness adds 25 minutes with probability 0.20. Closure adds ten minutes and $2 with probability 0.15. Assume the two events are independent and the stated fallback is usable. The working target is 110 minutes; Alex’s hard limits are 120 minutes and $20.

Model supplied
List on-time/open, on-time/closed, late/open and late/closed. Multiply the independent branch probabilities, then sum only outcomes with duration strictly greater than 110 minutes.

What is the probability of exceeding 110 minutes, as a percentage? Enter the number only, without a % sign.

Probability of duration > 110 minutes (%)

Enter one number. A calculator and your lecture notes are welcome.

Case 04 / 06The average approves a different tail

Separate marginal means from joint risk

Keep Case 3’s base, increments and lateness probability of 0.20. Replace independence with P(closed | late) = 0.50 and P(closed | on time) = 0.0625. A teammate argues that if the mean duration is unchanged, the chance of missing the working target must be unchanged too.

Model supplied
P(closed) = P(late)P(closed | late) + P(on time)P(closed | on time). With additive consequences, E(T) = 85 + 25P(late) + 10P(closed).

Which report correctly compares this changed model with Case 3?

AClosure stays 15%, so both the mean duration and the >110-minute probability must stay unchanged.BClosure stays 15%; means stay $18.30 and 91.5 minutes. The >110-minute probability rises from 3% to 10%.CClosure becomes 56.25% by adding the two conditional probabilities directly.DThe mean is below 110 minutes, so neither model can produce a duration above 110.

Case 05 / 06The backup venue appoints itself

Recheck changed fallbacks before revising a plan

Before departure, a fallback recheck changes Case 3’s closure increment from ten to 25 minutes. The late increment remains 25 minutes, the base remains 85, and the fallback exit is now unverified. A teammate proposes moving the confirmed plan there automatically because it still costs at most $20.

Which response handles the changed route and agreement?

ASwitch automatically: naming an alternative in the earlier plan pre-authorises all of its changed terms.BKeep the fallback because the $20 budget passes; ignore the duration and exit checks.CApprove the fallback whenever its expected duration is under 120 minutes, regardless of individual outcomes.DLate plus closed now takes 135 minutes, and the exit check fails. Find a feasible checked alternative and obtain fresh versioned agreement, or cancel.

Case 06 / 06The confirmation clock closes the ticket

Preserve deadline, cancellation and review transitions

Each branch starts from a separate proposed plan q1, with Alex’s confirmation at 16:20. Its confirmation point is 16:40 and departure is 17:00. Every counterpart confirmation names q1. Review updates concern the same replied Week 8 record. Read times as minutes on the proposal day, not hours since an opener.

Independent branches · all events have new IDs and chronological times

Branch	Next events
A	Counterpart confirms 16:39
B	Counterpart confirms 16:40
C	Cancel 16:30; counterpart confirms 16:35
D	Review hold 16:30; complete clearance 16:35

Which final states and Week 10 export decision follow the contract?

AA and B are confirmed; C and D can reuse Alex’s earlier confirmation to finish later.BA confirmed; B expired; C cancelled; D draft with no confirmations. Only A can be exported as a currently agreed plan.CA, B and C are confirmed because the latest confirmation wins; D returns to proposed with Alex still confirmed.DA confirmed; B expired; C cancelled; D restores the earlier proposed plan with Alex’s confirmation intact.

Reveal answers

Answer all 6 cases to unlock your score and the worked explanations.