# Analyze — overview & patterns
This section ties together the shortcuts across `Table`, `Statistics`, and `Analyze`.
## From Table to analysis
```js
import { Table } from 'als-statistics';
import { Analyze } from 'als-statistics';
const t = new Table(data, { name: 'Survey' });
// Correlation (single pair)
const r1 = t.correlate('height','weight').pearson();
// Correlation matrix (3+ columns)
const rAll = t.correlate('height','weight','age').pearson();
// Compare means (Welch, unequal variances)
const w = t.compareMeans('groupA','groupB').independentWelch();
// One-way ANOVA (classic/Welch)
const a1 = t.compareMeans('A','B','C').anova();
const aW = t.compareMeans('A','B','C').anovaWelch();
// Regression (linear/logistic)
const lin = new Analyze.Regression(t.columns, { yName:'score', xNames:['age','hours'] });
const log = new Analyze.Regression(t.columns, { yName:'passed', xNames:['score'], type:'logistic' });
```
## Split → Combine (Statistics) → Analyze
```js
// Split one table by a factor (returns Statistics with per-group tables)
const S = t.splitBy('group', { 0:'ctrl', 1:'treat' });
// Combine the same column across all split tables into one Table
const merged = S.columns('byGroup', 'score'); // -> ctrl_score, treat_score
// Now analyze as usual
const test = merged.compareMeans('ctrl_score','treat_score').independentWelch();
```
> Keep **mutations** API-only (`addRow`, `setAt`, `splice`, `values=`). Avoid in-place array edits to preserve caches and consistent results.