time_series_with_matrices#

  • Series: lecture-python-intro

  • File: lectures/time_series_with_matrices.md

  • Audit date: 2026-05-28

  • Categories audited: writing, math, code, figures, references, links, admonitions (JAX out of scope)

  • Overall score: 5.9 / 10

  • Priority: MEDIUM

Score breakdown#

Category

Score

One-line note

Writing

7/10

H1 Title Case OK; H2 sentence case mostly; minor multi-sentence paragraphs.

Math

4/10

Heavy use of \begin{array} for matrices (M4); ^T for transpose (M2); \mathcal N for normal distribution (M9).

Code

9/10

Unicode Greek (α, β, σ, y) used throughout (qe-code-002 OK); standard Anaconda imports.

JAX

out of scope

—

Figures

7/10

figsize= on line 54 only; no ax.set_title/spines violations; no {figure} directives.

References

8/10

1 {cite} usage (parenthetical, OK).

Links

4/10

3 direct URLs to python.quantecon.org on lines 371, 526, 541 — should be {doc} links.

Admonitions

N/A

no exercises / solutions

Issues#

Critical#

None found.

High severity#

  • M4 — Uses \begin{array} instead of \begin{bmatrix} for matrix display throughout. Examples: lines 93–115, 284, 613–625. Count: 6+ matrix blocks.

  • M2 — Uses ^T for transpose (line 394: \tilde A (\sigma_u^2 I_{T \times T} ) \tilde A^T).

  • [qe-link-002] — 3 cross-series direct URLs that should be {doc} links. Examples: lectures/time_series_with_matrices.md:371 ([Multivariate Normal Distribution](https://python.quantecon.org/multivariate_normal.html)), 526, 541. Count: 3 occurrences.

Medium severity#

  • M9 — Distribution name uses \mathcal{N} (line 382: y \sim {\mathcal N}(\mu_y, \Sigma_y)); should be plain N.

Low severity#

  • W1 — Some short two-sentence paragraphs (e.g. lines 33–36).

  • [qe-fig-001] — figsize= on line 54. Count: 1 occurrence.

  • [qe-fig-005] — No figures use {figure} directive with :name:.

Strengths#

  • H1 Title Case OK.

  • Equation labels with {math} :label:.

  • IID written correctly (line 275 via ref).

  • Italic for emphasis (initial conditions, terminal conditions).

  • Unicode Greek in code throughout.