Analytics
496 bites tagged Analytics: interview questions with model answers, and 60-second explainers.
Test yourself: Top 30 Analytics interview questions →Multiple choice, with the correct answer and why it is correct on every question. Free, no sign-in.Amplitude reduces MCP tool overload by grouping actions around usage
Amplitude redesigned its MCP server after endpoint-level tools created context bloat and tool-choice errors.
Jev catches changes in an analytics test, but false alarms matter
Amplitude reports a synthetic analytics benchmark. Strong recall alone does not prove reliable production analysis.
Re-evaluating personas when engagement is low
Bring behavioral evidence, separate persona-wrong from execution-wrong, propose joint research to validate or invalidate.
Unify behavior, billing, and CRM data
Ingest events, sync Stripe and Salesforce into a warehouse, resolve identities to one customer, model unified metrics.
Instrument an onboarding flow for analytics
Track each onboarding step plus the activation milestone, define a clean event schema with stable IDs, send reliably via batching or server-side.
Measuring design system documentation effectiveness
Search-with-no-results, time-to-first-component, support-ticket deflection, tied to analytics and registry data.
Sessionizing clickstream events into sessions
Order events per user, split on inactivity gap, assign session ids, pick event or session grain.
Data warehouse vs data lake
Warehouses store structured, schema-on-write data for BI; lakes store raw multi-format data with schema-on-read for exploration and ML.
What is an OLAP cube and its operations?
A cube pre-aggregates measures across dimensions; operations are slice, dice, drill-down, roll-up, and pivot.
Visualizing long-term trend versus seasonality
A line chart over the full three years, often with a moving average, shows the long-term trend; a seasonal plot overlaying each year by month, or a month-of-year box plot, reveals…
Track scroll depth: Intersection Observer vs scroll events
Place sentinels at depth thresholds and fire once via Intersection Observer, off the main thread; scroll listeners fire constantly and need throttling.
Build a simple A/B test for a headline
Assign each visitor a sticky bucket, serve the matching headline variant, log impressions and conversions per variant.
CSV vs JSON vs Parquet for analytics
CSV and JSON are row-based, human-readable, and bulky; columnar Parquet/ORC compress well and read only needed columns; choose columnar for analytics.
Data lake versus data warehouse
Lakes store raw, schema-on-read data of any type cheaply; warehouses store curated, schema-on-write structured data for fast SQL; choose a lake for varied raw data and ML.
Calculating Daily Active Users in SQL
Need per-event user_id and timestamp and a clear active definition; count distinct user_id within the day in a fixed timezone.
Client vs server tracking: pros, cons, examples
Client-side wins on UI context but loses data to blockers and tampering; server-side wins on reliability and trust but misses pure UI events.
Building a conversion funnel in SQL
Count distinct users reaching each ordered step, compute step-over-step conversion; the biggest drop-off is the lowest consecutive ratio.
Investigating analytics vs database count gaps
Causes include ad-blocker loss, differing identity logic, timezone mismatches, filtering, and pipeline delay; investigate by aligning definitions and tracing one user.
SQL for a three-step onboarding funnel
Anchor the 30-day signup cohort, count distinct users reaching each later step in timestamp order; conversion is each step over the prior.
Visualizing a correlation with a third variable
A scatter plot with a trend line shows the relationship; encode network type by color or facets to expose a lurking variable.
Cohort analysis for an onboarding change
A cohort groups users by a shared start trait; compare pre and post Jan-1 signup cohorts on retention by age.
Visualizing a non-linear funnel with re-entry
A linear funnel cannot show branching or re-entry; a Sankey diagram encodes flow volume, splits, and leaks as proportional ribbons.
Designing a useful button_click event payload
Include identity, timestamp, and context plus properties like button id, screen, and state; govern with a naming convention.
Designing a warehouse model for feature adoption
Star schema with a feature-usage fact table at a defined grain, surrounded by user, feature, date, and device dimensions.
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