Product Analytics: Data-Driven Decision Making

// Key metrics to track
interface ProductMetrics {
  acquisition: number;      // New users
  activation: number;       // Users who reach AHA moment
  retention: number;        // Users who return
  revenue: number;          // Revenue generated
  referral: number;         // Users who refer others
}

// Track where users come from
function trackAcquisition(source: string) {
  analytics.track('user_acquired', {
    source,
    medium: 'organic',
    campaign: null,
    timestamp: new Date()
  });
}

// Measure conversion rate
const conversionRate = (signUps / visitors) * 100;

// Track user activation
function trackActivation(userId: string, action: string) {
  analytics.track('user_activated', {
    userId,
    activationAction: action,
    timeToActivation: calculateTimeToActivation(userId)
  });
}

// AHA moment example
const isActivated = user.postsCreated >= 3;

// Cohort analysis
function calculateRetention(cohort: Date[]): number[][] {
  const retention: number[][] = [];
  
  for (let week = 0; week < 8; week++) {
    const activeUsers = cohort.filter(user => 
      isActive(user, week)
    ).length;
    
    retention[week] = [week, (activeUsers / cohort.length) * 100];
  }
  
  return retention;
}

// Retention rate
const retentionRate = (returningUsers / totalUsers) * 100;

// Custom event tracking
class AnalyticsTracker {
  track(eventName: string, properties?: Record<string, any>) {
    const event = {
      name: eventName,
      properties: {
        ...properties,
        timestamp: new Date(),
        userId: this.getUserId(),
        sessionId: this.getSessionId()
      }
    };
    
    this.send(event);
  }
  
  trackPageView(page: string) {
    this.track('page_view', { page });
  }
  
  trackButtonClick(buttonId: string) {
    this.track('button_click', { buttonId });
  }
}

interface FunnelStep {
  name: string;
  event: string;
  users: number;
}

function analyzeFunnel(steps: FunnelStep[]) {
  const conversion = [];
  let previousUsers = Infinity;
  
  for (const step of steps) {
    const stepConversion = (step.users / previousUsers) * 100;
    conversion.push({
      step: step.name,
      users: step.users,
      conversion: stepConversion,
      dropOff: 100 - stepConversion
    });
    
    previousUsers = step.users;
  }
  
  return conversion;
}

interface Experiment {
  name: string;
  variants: string[];
  metrics: string[];
  trafficSplit: number[];
}

function runExperiment(experiment: Experiment) {
  const variant = assignVariant(experiment.trafficSplit);
  
  // Track assignment
  analytics.track('experiment_viewed', {
    experiment: experiment.name,
    variant
  });
  
  // Track metrics
  for (const metric of experiment.metrics) {
    analytics.track(`metric_${metric}`, {
      experiment: experiment.name,
      variant,
      value: calculateMetric(metric)
    });
  }
}

function segmentUsers(users: User[]) {
  return {
    powerUsers: users.filter(u => u.loginCount > 20),
    casualUsers: users.filter(u => u.loginCount > 5 && u.loginCount <= 20),
    atRiskUsers: users.filter(u => u.loginCount > 0 && u.loginCount <= 5),
    churnedUsers: users.filter(u => u.loginCount === 0)
  };
}