Track D assignments: labs + rubric (TA)

This page turns Track D into a gradeable lab sequence.

  • Students produce a small set of files under outputs/track_d/.

  • Students answer a few short prompts (and write one short memo).

  • TAs can grade quickly with a clear checklist + rubric.

If students are new to Track D, point them to:

Prerequisites (students)

Students should start from a fresh Track D workbook folder created by:

pystatsv1 workbook init --track d --dest track_d_workbook
cd track_d_workbook

All labs below assume the default Track D scripts in that folder.

Submission format

Ask students to submit one ZIP file containing:

  1. outputs/track_d/ (artifacts)

  2. answers.md (short answers for Labs 1–3)

Suggested ZIP command (from the workbook folder):

# Windows PowerShell (inside track_d_workbook)
Compress-Archive -Path outputs/track_d,answers.md -DestinationPath track_d_submission.zip -Force

# macOS/Linux (inside track_d_workbook)
zip -r track_d_submission.zip outputs/track_d answers.md

Lab 1 — Run + interpret outputs

Goal

Students can run Track D, locate outputs, and explain the key metrics in plain language.

Run

From the Track D workbook folder:

pystatsv1 workbook run d00_peek_data
pystatsv1 workbook run d01

Required artifacts

Students must include these files in outputs/track_d/:

  • d00_peek_data_summary.md

  • business_ch01_summary.json

  • business_ch01_income_statement.png

  • business_ch01_balance_sheet.png

Short answers (write in answers.md)

Answer in 1–3 sentences each.

  1. Where do outputs land? - Give the exact folder path (relative to the workbook).

  2. Net income can be negative. Why? - Explain one realistic reason a startup month might show negative net income.

  3. Gross margin, in plain language. - What is it, and why do analysts care?

  4. What does ``pct_sales_on_account`` mean? - Explain it as if you were speaking to a non-accountant manager.

  5. What good looks like (sanity checks). - List 2 checks you can run (or observe) that increase confidence you didn’t break the data.

TA quick-check (optional)

For the stock Track D case, d01 prints a small “sanity summary” to the terminal that includes n_transactions and whether the accounting equation balances. Students do not need exact matching numbers, but their explanations should be consistent.

Lab 2 — QC detective: duplicate bank transaction IDs

Goal

Students demonstrate “accounting-data analyst” habits: identify a QC issue, explain why it matters, and propose a defensible fix.

Task

Using the NSO v1 bank statement table (from the Track D dataset), find a duplicated transaction identifier and document it.

Students may use any method (spreadsheet filter, Python, etc.). Here is an optional Python snippet they can adapt:

import pandas as pd
p = "data/synthetic/nso_v1/bank_statement.csv"
df = pd.read_csv(p)
dup = df[df.duplicated("bank_txn_id", keep=False)].sort_values("bank_txn_id")
print(dup[["bank_txn_id","date","amount","description"]].head(20))

Required artifacts

Students must include in outputs/track_d/:

  • lab2_qc_report.md (their QC write-up)

Their report must include:

  • the duplicated bank_txn_id value(s)

  • how many rows were duplicated

  • why the duplication matters (what could go wrong downstream)

  • a proposed fix policy (example: “drop exact duplicates”, or “keep the earliest posted row”)

  • one “before vs after” check (example: total cash inflow/outflow changes, or count of transactions)

Short answers (write in answers.md)

  1. What did you find? - One sentence summary of the duplicate.

  2. What could break if we ignore it? - Name one analysis result that could be distorted.

  3. What fix policy did you choose and why?

Lab 3 — Executive summary memo

Goal

Students turn outputs into a clear, decision-friendly narrative.

Prompt

Write a 250–400 word memo (in answers.md) titled:

“Track D Executive Summary (Month 1)”

Use the Lab 1 outputs (plots + JSON summary) and include:

  • 2–3 key facts about sales, gross margin, and expenses

  • net income interpretation (including why it may be negative)

  • 1 balance sheet insight (example: cash position, liabilities, equity)

  • 2 “next questions” you’d ask before making a real decision

Rubric (100 points)

This rubric is designed to be fast to grade.

Artifacts + reproducibility (30)

    1. Required Lab 1 artifacts present in outputs/track_d/

    1. Lab 2 QC report present and complete

    1. Student’s answers.md is organized with headings for Lab 1–3

Interpretation of outputs (30)

    1. Net income explanation is realistic and correctly framed

    1. Gross margin explained correctly (and why it matters)

    1. pct_sales_on_account explained correctly and connected to business meaning

QC reasoning (20)

    1. Duplicate ID issue clearly demonstrated with evidence

    1. Fix policy is defensible; “before vs after” check is included

Communication quality (20)

    1. Executive memo is clear, concise, and decision-oriented

    1. Writing uses plain language, defines terms, and avoids jargon where possible

Extensions (optional)

If you want to stretch advanced students, ask for one extra artifact:

  • a small table (CSV) that summarizes totals by month (or by account)

But the core labs above are intentionally minimal so students can complete them quickly.