College AI Track

Module 5 of 12

Module 05: Data Analysis for Any Major — Python, pandas, Visualization & AI-Assisted Analytics

4 min read715 words
What you'll learn
Load, inspect, and clean CSV/Excel-style tables with pandas.Compute descriptive stats and group summaries appropriate to your domain.Visualize with matplotlib (optional seaborn) using honest scales and source notes.Use AI as a calculator assistant—you specify design and verify assumptions.

"A chart is an argument about what deserves attention—and honest scales are part of that argument." — Paraphrasing stats and visualization educators

Duration: 7–9 hours · Difficulty: Intermediate · Prerequisites: Intro stats comfort; Python 3.10+ in a venv.

Learning Objectives

By the end of this module, you will be able to:

  1. Load, inspect, and clean CSV/Excel-style tables with pandas.
  2. Compute descriptive stats and group summaries appropriate to your domain.
  3. Visualize with matplotlib (optional seaborn) using honest scales and source notes.
  4. Use AI as a calculator assistant—you specify design and verify assumptions.
  5. Compare Excel, Python, and “full AI pipeline” workflows—and know where AI misleads on causality and joins.

Concept 1: Why Python + pandas

DimensionExcelPython/pandasAI assistant
First plotFastSlower setupFast if schema clear
ReproducibilityManual riskGit + scriptsWeak unless you save code
Complex joinsError-prone at scaleExplicitMay hallucinate columns
StatsToolpack / formulasscipy/statsmodelsMay pick wrong test

Concept: Print df.shape after every merge—row-count surprises catch silent drops or explosions.

Messy data → first check

SymptomFirst checkTypical fix
Weird summariesdescribe(include="all")Coerce dtypes
Merge explodedlen before/afterKey duplicates
Empty chartNA fractionFilter or document imputation

Concept 2: Question → Report

  1. Define question and unit of analysis (one row = ?). 2. Ingest with source + date. 3. Profile missingness, dtypes, dupes. 4. Transform with formulas in comments. 5. Analyze; visualize; report magnitude and limitations.

Associational trap: “Library hours vs GPA” ignores self-selection—frame as association, not cause, unless design supports more.

Pitfalls vs AI

PitfallAI might tempt you to…
ConfoundingOversimple regression
p-hackingRun many tests silently
Ecological fallacyConfuse group and individual

Concept 3: Visualization with AI

Sketch chart intent in chat; implement in your matplotlib. Checklist: meaningful zero baseline for counts; units on axes; n in caption; source line.

Environment Setup (plain instructions)

bash
python -m venv .venv
,[object Object],
pip install pandas matplotlib openpyxl

Hands-On: Load and Profile

Key Example: This pattern is the spine of most course projects—everything else is filtering, grouping, and plotting.

python
[object Object], pandas ,[object Object], pd

df = pd.read_csv(,[object Object],)
,[object Object],(df.shape)
,[object Object],(df.columns.tolist())
,[object Object],(df.dtypes)
,[object Object],(df.isna().mean().sort_values(ascending=,[object Object],).head())

In words: After read_csv, always check shape, dtypes, and missingness before plotting—otherwise charts lie because "12" is still a string. Group with groupby(...).agg(...), merge with explicit how= and row-count checks, plot with title, xlabel, ylabel, and savefig at 150–300 DPI when final.

Try This! Ask ChatGPT for pandas for your schema—then run head(), assert row counts, and grep column names against the real CSV header.

Fun Fact: Mean of ratios ≠ ratio of means—your caption should say which denominator you used.

Dashboards for coursework

A “dashboard” can be one figure with 2×2 panels: KPI text, distribution, breakdown by category, missingness bars—or a short HTML/PDF export from Jupyter/Quarto.

Presenting findings

Slides: Question → one clean figure → methods in five bullets → limitations → one “so what.” Executive summary: three numbers max with context for a non-technical reader.

Try This Now

  1. Data dictionary before any plot.
  2. Join lab — predict inner vs outer counts on toy CSVs.
  3. Misleading chart online → redraw ethically; two sentences on what changed.

Practice Exercises

Data dictionary; join sanity; misleading chart fix; aggregation puzzle (mean of ratios vs ratio of means); AI code review log with three verified flags.

Mini-Project

Notebook: ≥3 visualizations with magnitude-aware captions; methods 300–500 words (source, cleaning, bias); one-page executive summary; optional AI disclosure for code help.

Key Takeaways

  • Reproducibility is kindness to graders and future you.
  • Visualization is argument—axes and n matter.
  • Statistics without design is storytelling—name bias early.

Key Takeaway

  • Use Excel for speed, Python for repeatability, AI for boilerplate—you always verify joins and tests.
  • Label charts with units, source, and sample definition; call out non-causal scatter plots honestly.
  • Dtypes and missingness before pretty pictures—fix coercion first.
  • Treat AI-suggested analyses as drafts until assumptions match your study design.
  • Ship a limitations paragraph—mature projects own what the data cannot prove.

Resources

Appendix: Sample public data sources

SourceNote
data.govCheck update frequency
Campus open dataAggregate; FERPA norms
KaggleCite honestly in coursework

Record access date and license in methods.