A/B Testing

HapticExperiment lets you A/B test different haptic patterns to determine which users prefer. It handles variant assignment, event tracking, and results aggregation.

Setup

import { HapticExperiment, haptic } from '@hapticjs/core';

const experiment = new HapticExperiment('checkout-feedback', {
  a: '~~..##',          // HPL string
  b: '@@',              // Another HPL string
  c: '|..|..|',         // A third variant
});

Variants can be HPL strings, HapticPattern objects, or HapticStep[] arrays.

Assigning Variants

// Deterministic assignment based on user ID (consistent via hash)
const variant = experiment.assign('user-123');  // 'a', 'b', or 'c'

// Same user always gets the same variant
experiment.assign('user-123'); // Same result as above

// Anonymous assignment (random)
const anonVariant = experiment.assign();

Playing the Assigned Pattern

const userId = 'user-123';
experiment.assign(userId);

const pattern = experiment.getVariant(userId);
if (pattern) {
  haptic.play(pattern);
}

Tracking Events

Track user actions to measure which variant performs better:

// Track conversion
experiment.track('user-123', 'conversion');

// Track engagement
experiment.track('user-123', 'button-click');

// Track with a numeric value
experiment.track('user-123', 'satisfaction', 4.5);

Getting Results

const results = experiment.getResults();
// {
//   a: { assignments: 15, events: { conversion: 8, 'button-click': 12 } },
//   b: { assignments: 14, events: { conversion: 11, 'button-click': 10 } },
//   c: { assignments: 13, events: { conversion: 6, 'button-click': 9 } },
// }

Properties and Methods

Member	Description
name	Experiment name
assign(userId?)	Assign a variant (deterministic per user ID)
getVariant(userId)	Get the pattern for an assigned user
track(userId, event, value?)	Track an event
getResults()	Get aggregated results per variant
reset()	Clear all assignments and tracking data

Full Example

import { HapticExperiment, haptic, presets } from '@hapticjs/core';

// Test which notification pattern leads to more conversions
const experiment = new HapticExperiment('notification-haptic', {
  subtle: presets.notifications.info,
  standard: presets.notifications.success,
  strong: presets.notifications.alarm,
});

function onCheckout(userId: string) {
  // Assign and play the variant
  const variant = experiment.assign(userId);
  const pattern = experiment.getVariant(userId);
  if (pattern) {
    haptic.play(pattern);
  }

  console.log(`User ${userId} assigned to variant: ${variant}`);
}

function onPurchaseComplete(userId: string) {
  // Track the conversion
  experiment.track(userId, 'purchase');
}

// Later, analyze results
function analyzeExperiment() {
  const results = experiment.getResults();

  for (const [variant, data] of Object.entries(results)) {
    const conversionRate = (data.events.purchase ?? 0) / data.assignments;
    console.log(`${variant}: ${(conversionRate * 100).toFixed(1)}% conversion`);
  }
}

TIP

The assignment hash is deterministic -- the same userId always maps to the same variant within the same experiment. This ensures consistent user experiences across sessions.

INFO

HapticExperiment stores data in-memory. For production, persist getResults() to your analytics backend.

Related

• Presets -- Use presets as experiment variants
• Pattern Recorder -- Record custom patterns to test
• Middleware -- Transform patterns before playback