10 / 18 · One-way ANOVA

Report variance assumptions and pairwise corrections together

Present group distributions with multiplicity-corrected contrast intervals. Keep the overall F test separate from each pairwise conclusion.

Classical F + Tukey · 944 respondents · ANES96

 Report variance assumptions and pairwise corrections together
This preview shows the existing 16:9 slide. The Pele map below did not generate the full statistical chart.

This companion diagram explains variables, design and tests. It is distinct from the statistical figure in the standalone presentation.

 Analysis relationship map
Groups: 1 = high school or less; 2 = some college; 3 = degree+. Bars show within-group frequencies; contrasts use the selected correction.
Pele map source
flowchart LR
 E["Education3groups"] --> Y["TV-news distribution"]
 Y --> F["Overall F"]
 Y --> P["Corrected pair contrasts"]
 P --> C["Uncertainty retained"]

This actual production branch takes computed estimates and places axes, lines, intervals and labels. Shared helpers and the complete file are available below.

SVG construction branch · JavaScript
if (v.kind === "anova") {
  a.push(
    T(0, 35, "A  Actual0–7 times distributions", 30, C.ink, 700),
    T(900, 35, "B  Familywise mean contrasts", 30, C.ink, 700),
  );
  const cols = [C.blue, C.teal, C.slate];
  v.groups.forEach((g, i) => {
    let yy = 105 + i * 155;
    a.push(
      T(0, yy, g.label, 28, C.ink, 650),
      T(0, yy + 37, "n " + g.n + " · mean " + fmt(g.mean, 2), 25, C.muted),
    );
    for (let d = 0; d < 8; d++) {
      let n = g.hist.find((a) => a[0] === d)?.[1] || 0,
        h = (n / g.n) * 155;
      a.push(
        G(
          [
            R(370 + d * 56, yy + 85 - h, 40, h, cols[i]),
            T(390 + d * 56, yy + 118, String(d), 22, C.muted, 400, "middle"),
          ],
          g.key,
        ),
      );
    }
  });
  a.push(
    ...forest(v.contrasts, {
      x: 900,
      y: 50,
      w: 700,
      labelW: 130,
      rowH: 115,
      title: "",
      unit: "Times/week · corrected95% CI",
    }),
    T(
      905,
      560,
      "F(" + v.df.map((x) => fmt(x, 1)).join(", ") + ") = " + fmt(v.F, 3),
      27,
      C.ink,
      650,
    ),
    T(
      905,
      605,
      pv(v.p) + " · descriptive η² " + fmt(v.eta2Descriptive, 4),
      26,
      C.muted,
    ),
  );
  note =
    "Groups: 1 = high school or less; 2 = some college; 3 = degree+. Bars show within-group frequencies; contrasts use the selected correction.";
  source =
    'flowchart LR\n E["Education3groups"] --> Y["TV-news distribution"]\n Y --> F["Overall F"]\n Y --> P["Corrected pair contrasts"]\n P --> C["Uncertainty retained"]';
  map = { E: v.groups[0].key, Y: v.groups[1].key, F: v.key, P: v.key, C: v.key };
}

This is preserved reference code, not an executable editor.

Data
Inspect the condition data first. Replace sample, units, coefficients and confidence intervals together. Do not combine different samples or measurement levels on one scale.
Graphic
Fit axis ranges, label widths, type and colors to the target region. Preserve whether intervals include zero and recheck legibility at the final size.
Interpretation
Diagram arrows and model paths are not causal evidence. Distinguish mean-response from prediction intervals, and pointwise from simultaneous intervals.