als-statistics/tests/golden/tools/cronbach.js

Modular JS statistics toolkit for Node.js and the browser: descriptive stats, correlations (Pearson/Spearman/Kendall), t-tests & ANOVA (Student/Welch), reliability (Cronbach’s alpha), regression (linear/logistic), clustering (DBSCAN/HDBSCAN), and table/co

import { CronbachAlpha } from '../../../lib/analyze/correlate/cronbach-alpha.js';
import { makeRng } from '../_rng.js';

export const cronbachTool = {
  id: 'cronbach',
  cases: 5,
  gen(seed, i) {
    const R = makeRng(`${seed}/cr/${i}`);
    const n = 15 + (i % 4);   // респондентов
    const k = 4 + (i % 3);    // пунктов
    const table = {};
    for (let j=0; j<k; j++) {
      const base  = R.normal(50, 10, n);
      const noise = R.normal(0, 5 + 2*((j+i)%2), n);
      table['Q'+(j+1)] = base.map((x, idx) => x + noise[idx]);
    }
    return table;
  },
  compute(table) {
    const ca = new CronbachAlpha(table);
    return { alpha: ca.alpha };
  },
  compare(exp, got, approx) {
    approx(got.alpha, exp.alpha);
  },
};