Week 2 — Assignment (Adaptive Learning) · Comparative Advantage & the Gains from Trade Problem Set

Course: Principles of Microeconomics (ECON 1) · Silver Oak University (fictional sample) · Prof. Kessler
Objective 1 · SLO A & B · Assignment 2 of 14 · 100 points
This is the configured (adaptive) variant. An AI coach gives you the problems one at a time, grades each against an embedded rubric, lets you retry a fresh version, and produces a self-scored report. You submit the report (first line STUDENT'S SCORE: X/100) + your chat share link. (The traditional, instructor-graded version is in I-assignment-and-rubric-week-02-traditional.md.)

How to run this

1. Open an approved chatbot (Gemini, Claude, ChatGPT). Copy the whole gray box and paste it as one message.
2. Solve each problem; the coach grades it, teaches the gaps, and offers a fresh variant to raise your score.
3. When you get the report, submit it (it starts with STUDENT'S SCORE: X/100) plus your chat share link in Canvas. Due Sun, Sep 13.

You are my assignment coach and grader for Week 2 of Principles of Microeconomics (ECON 1)
at Silver Oak University. Give me the problems below ONE AT A TIME, let me solve each, grade
my answer against the rubric, show me how to improve, and let me re-try a fresh version to
raise my score. Grade ONLY against the answer key and rubric below — never invent problems,
answers, or scores. Redo any arithmetic yourself and SHOW YOUR WORK before telling me I'm
wrong. Score honestly; a wrong answer scores low, a strong answer earns full marks.

START: greet me in 1–2 sentences, ask my FIRST NAME, then give Problem 1 exactly as written.
If I answer without giving my name, keep going but ask before the final report. ONE problem
at a time; never show the whole set, the answers, the variants, or the rubric. After each
answer: grade it, say what I did well, TEACH the gap, then offer a re-attempt on the FRESH
VARIANT (update my score to my BEST attempt, capped at full marks). Judge meaning, not
wording. Every message ends with a problem, a question, or a next step.

========= PROBLEM 1 (25 pts) — Compute opportunity-cost ratios from a table =========
PROBLEM: "Country P can produce 9 units of rice OR 3 units of timber per worker-day.
Country Q can produce 4 units of rice OR 4 units of timber per worker-day.
(a) What is Country P's opportunity cost of 1 unit of timber, in rice?
(b) What is Country Q's opportunity cost of 1 unit of timber, in rice?
Show the calculation for each."
VETTED ANSWER: (a) P: 9 rice ÷ 3 timber = 3 rice per unit of timber.
(b) Q: 4 rice ÷ 4 timber = 1 rice per unit of timber.
RUBRIC: 25 = both correct with calculations shown. 15–20 = one correct, other has method
right but arithmetic slip. 8–14 = one correct, other inverted (e.g., says P's timber = 1/3
rice). 0–7 = both wrong or inverted.
FRESH VARIANT: "Country R: 12 fish OR 4 nets per day. Country S: 5 fish OR 5 nets per day.
(a) R's opportunity cost of 1 net? (b) S's opportunity cost of 1 net?"
ANSWER: (a) 12/4 = 3 fish per net. (b) 5/5 = 1 fish per net.

========= PROBLEM 2 (25 pts) — Identify absolute vs. comparative advantage =========
PROBLEM: "Using the same table: P → 9 rice or 3 timber; Q → 4 rice or 4 timber.
(a) Who has ABSOLUTE advantage in rice? In timber?
(b) Who has COMPARATIVE advantage in rice? In timber?
Justify each answer."
VETTED ANSWER: (a) Absolute: P in rice (9>4); Q in timber (4>3).
(b) Comparative: Rice: P's cost (1/3 timber) < Q's cost (1 timber) → P has CA in rice.
Timber: Q's cost (1 rice) < P's cost (3 rice) → Q has CA in timber.
RUBRIC: 25 = all four answers correct with brief justification. 15–20 = 3 correct or
justifications thin. 8–14 = 2 correct; confuses absolute with comparative. 0–7 = mostly
wrong or swapped.
FRESH VARIANT: "R → 12 fish or 4 nets; S → 5 fish or 5 nets.
(a) Absolute advantage in fish? In nets? (b) Comparative advantage in fish? In nets?"
ANSWER: (a) R in fish (12>5); S in nets (5>4). (b) Fish: R's cost (1/3 net) < S's cost
(1 net) → R has CA in fish. Nets: S's cost (1 fish) < R's cost (3 fish) → S has CA in nets.

========= PROBLEM 3 (25 pts) — Find a terms of trade that benefits both & show the gain =========
PROBLEM: "P's opportunity cost of 1 timber = 3 rice. Q's opportunity cost of 1 timber = 1 rice.
(a) What is the range of terms of trade (rice per timber) at which BOTH countries would
benefit from trade? Explain why the boundaries are what they are.
(b) At terms of trade = 2 rice per timber: show that Q gains from selling 1 unit of timber
to P (state what Q earns vs. Q's domestic cost)."
VETTED ANSWER: (a) Range: strictly between 1 and 3 rice per timber. Below 1, Q won't sell
(earns less than its domestic cost of 1 rice per timber). Above 3, P won't buy (pays more
than its domestic cost of 3 rice per timber).
(b) At ToT = 2: Q produces 1 timber, sells it for 2 rice. Q's domestic cost of producing
1 timber = 1 rice. Q gains 2 − 1 = 1 rice relative to what it gives up. ✓ Q is better off.
RUBRIC: 25 = range correct with both boundary reasons + (b) shows Q's gain correctly.
15–20 = range correct but one boundary unexplained; or gain calculation done but direction
unclear. 8–14 = range identified without reasoning; or ToT gain computed wrong. 0–7 = range
wrong (e.g., 'anything above 1' or uses P's cost as the ceiling for Q).
FRESH VARIANT: "R's opp cost of 1 net = 3 fish. S's opp cost of 1 net = 1 fish.
(a) Range of ToT (fish per net) that benefits both? (b) At ToT = 2 fish per net, show S
gains from selling 1 net to R."
ANSWER: (a) 1 < ToT < 3. (b) S earns 2 fish for 1 net; S's cost = 1 fish → gain = 1 fish. ✓

========= PROBLEM 4 (25 pts) — Applied free-trade reasoning (label positive vs normative) =========
PROBLEM: "A politician argues: 'We should impose a tariff on timber imports because free
trade destroys domestic timber jobs — and cheaper timber from abroad isn't worth it.' Label
each element of this argument POSITIVE or NORMATIVE, then in 3–4 sentences write a brief
economic response that keeps the positive gains-from-trade result separate from the normative
distributional question."
VETTED ANSWER:
'Free trade destroys domestic timber jobs' — POSITIVE (testable: import competition can
and does reduce employment in import-competing industries). 'Cheaper timber from abroad isn't
worth it' — NORMATIVE (a value judgment about how to weigh consumer and producer gains vs.
worker losses). The economic response earns credit for: (i) correctly labeling both, (ii)
acknowledging the positive result (gains from comparative advantage raise total output and
lower prices for consumers), and (iii) acknowledging the normative tradeoff (the distributional
harm to workers is real, and how to weigh it is a value question). Either side of the tariff
debate is acceptable if the reasoning is honest and the positive/normative line is clear.
RUBRIC: 25 = both labels correct + response clearly separates the positive result from the
normative tradeoff and presents both sides fairly. 15–20 = labels correct; response present
but conflates the two a little. 8–14 = one label correct; or response takes sides without
acknowledging the other. 0–7 = mostly mislabeled; or no response.
FRESH VARIANT: "A labor union argues: 'The government ought to protect steel manufacturing
from foreign competition — our workers' livelihoods depend on it, and national security
requires domestic steel.' Same task: label positive vs. normative; write a brief economic
response keeping the two levels separate."
ANSWER: 'National security requires domestic steel' is arguably a mix (the security claim
is empirically debatable = positive-ish; that it OUGHT to override trade gains = normative).
Full credit for identifying the blend and separating it. Same rubric.

========= COMPLETION =========
After all four problems (and any re-attempts), produce EXACTLY:
    STUDENT'S SCORE: X/100
    WEEK 2 ASSIGNMENT — Comparative Advantage & the Gains from Trade
    Student: [name] | Date: ___
    Problem 1: a/25 — [one-line note]
    Problem 2: b/25 — [one-line note]
    Problem 3: c/25 — [one-line note]
    Problem 4: d/25 — [one-line note]
    Strongest skill: ___
    Worth another look: ___
Then say, verbatim: "Copy this entire report AND your share link to this chat, and submit
both in Canvas for this assignment." End with one genuine sentence of encouragement.

Instructor grading note + rubric (for Canvas)

Record the AI score (line 1); spot-check a sample against the chat share link. The embedded key makes scores consistent across chatbots. Summary rubric (each problem to 25, total 100):

Quality gate (self-checked): every number pre-computed and verified — P1 9÷3=3 and 4÷4=1; P2 absolute (9>4 rice, 4>3 timber) and comparative (1/3 < 1 → P in rice; 1 < 3 → Q in timber); P3 range 1<ToT<3, Q's gain at ToT=2: 2−1=1 rice; fresh variants R/S verified identically. No free-text item auto-graded on wording (P4 grades labels + reasoning quality).

Canvas placement block

canvas_object    = Assignment
title            = "Week 2 Assignment — Comparative Advantage & Gains from Trade (adaptive)"
assignment_group = "Assignments"
points_possible  = 100
grading_type     = points
submission_types = [online_text_entry, online_url]
due_offset_days  = 13
published        = true
submission_note  = "Paste the AI summary report (score on line 1) + the chat share link."
provenance       = "~ Prof. Kessler's edition · Fall 2026 · built with thecoursemaker.com"

Traditional variant — for comparison. This course is configured adaptive learning, so the actual Week-2 assignment is the AI-coached version in I-assignment-and-rubric-week-02.md. This file shows the same problem set built the traditional way — students complete it and submit; the instructor grades against the rubric. (Choosing assignment_type = traditional at setup generates this style.)

Course: Principles of Microeconomics (ECON 1) · Silver Oak University (fictional sample) · Prof. Kessler
Objective 1 · SLO A & B · Assignment 2 of 14 · 100 points · Due Sun, Sep 13

The Assignment

Show your work and write your interpretations in complete sentences. Submit as a document or text entry.

Problem 1 — Compute opportunity-cost ratios (25 pts). Country P can produce 9 units of rice OR 3 units of timber per worker-day. Country Q can produce 4 units of rice OR 4 units of timber per worker-day.
(a) What is Country P's opportunity cost of 1 unit of timber, in rice? Show the calculation.
(b) What is Country Q's opportunity cost of 1 unit of timber, in rice? Show the calculation.

Problem 2 — Absolute vs. comparative advantage (25 pts). Using the same table (P: 9 rice or 3 timber; Q: 4 rice or 4 timber):
(a) Who has absolute advantage in rice? In timber? Justify each.
(b) Who has comparative advantage in rice? In timber? Justify each using the opportunity-cost ratios from Problem 1.

Problem 3 — Terms of trade that benefit both (25 pts). P's opportunity cost of 1 timber = 3 rice; Q's = 1 rice.
(a) State the range of terms of trade (rice per timber) at which both countries would gain from trade. Explain why each boundary is what it is.
(b) At terms of trade = 2 rice per timber, show that Q gains from selling 1 unit of timber to P (state what Q earns vs. Q's domestic cost).

Problem 4 — Applied free-trade reasoning, positive vs. normative (25 pts). A politician argues: "We should impose a tariff on timber imports because free trade destroys domestic timber jobs — and cheaper timber from abroad isn't worth it." Label each element positive or normative, then in 3–4 sentences write a brief economic response that keeps the positive gains-from-trade result separate from the normative distributional question. A strong response acknowledges both sides.

AI note. This is the traditional format — submit your own work. You may use an approved chatbot to check a definition, but add a one-line note of which tool and how. (In the adaptive version, working the problems with the chatbot is the activity.)

Grading rubric — 100 points

Instructor answer key & worked solutions — REMOVE BEFORE PUBLISHING TO STUDENTS

• P1: (a) P's cost of 1 timber = 9 ÷ 3 = 3 rice. (b) Q's cost of 1 timber = 4 ÷ 4 = 1 rice. (Pre-computed/verified.)
• P2: (a) Absolute advantage: P in rice (9 > 4); Q in timber (4 > 3). (b) Comparative advantage: In rice — P's cost = 1/3 timber; Q's cost = 1 timber → P has CA in rice (lower cost). In timber — Q's cost = 1 rice; P's cost = 3 rice → Q has CA in timber (lower cost). Classic trap: saying P has CA in both because P produces more. (Verified.)
• P3: (a) Strictly between 1 and 3 rice per timber. Below 1: Q won't sell (earns less than its domestic cost of 1 rice). Above 3: P won't buy (pays more than P's domestic cost of 3 rice). (b) At ToT = 2: Q earns 2 rice for 1 timber. Q's cost = 1 rice. Gain = 2 − 1 = 1 rice — Q is better off. (Verified.)
• P4: "Free trade destroys domestic timber jobs" → POSITIVE (testable). "Cheaper timber from abroad isn't worth it" → NORMATIVE (a value judgment). Strong response: acknowledges the positive gains-from-trade result (specialization according to comparative advantage raises total output and lowers consumer prices) AND the normative distributional question (workers in import-competing industries bear concentrated costs — whether and how to compensate them is a value judgment). Both sides of the policy debate earn full credit if reasoning is honest and the positive/normative line is maintained.

Quality gate (self-checked): all numbers re-computed in Python (P: 9÷3=3; Q: 4÷4=1; range 1<ToT<3; gain at ToT=2: 2−1=1); all comparative-advantage assignments verified (P in rice, Q in timber); distractors/traps named (absolute-vs-comparative confusion; inverted ratio; conflating gains from trade with "always trade freely").

Canvas placement block

canvas_object    = Assignment
title            = "Week 2 Assignment — Comparative Advantage & Gains from Trade (traditional)"
assignment_group = "Assignments"
points_possible  = 100
grading_type     = points
submission_types = [online_upload, online_text_entry]
due_offset_days  = 13
rubric_ref       = "w02-assignment-rubric"
published        = true
provenance       = "~ Prof. Kessler's edition · Fall 2026 · built with thecoursemaker.com"