Concepts in Analytics & Metrics, page 3
Data Anonymization: Protecting Privacy by Removing PII
Data anonymization breaks the link between data and real people by removing personal identifiers. It’s used to share datasets for research or analytics while protecting privacy.
GDPR: Treating User Data as a Liability, Not an Asset
GDPR treats personal data as a liability borrowed from the user. It gives EU citizens strong rights over their data, like access and erasure, forcing any company processing it to comply. The footgun is assuming it doesn't apply if your company isn't in the EU.
Data Governance: Corporate Management vs. Global Policy
Data governance operates at two scales: managing data within a company and setting data policy between nations. It applies to corporate data management and international internet governance.
Master Data Management (MDM): The Single Source of Truth
Master Data Management (MDM) creates a single source of truth for core business entities. It's used when departments have conflicting data (e.g., 'ACME Inc.' vs 'Acme Corp').
Data Stewardship: The Librarian for Your Data
A data steward is the designated owner of a data asset, responsible for its quality and business value, not just its storage. This role is crucial where data is shared across teams, ensuring consistency.
Data Masking: Protect Data, Preserve Utility
Data masking creates a realistic but fake version of your data by scrambling sensitive fields. It's used to give developers and analysts safe datasets for testing or analytics without exposing real PII.
Report Generation: Turning Raw Data into Human-Readable Documents
Report generators translate raw data into formatted documents for human eyes. They power business dashboards and sales summaries. The main footgun is forgetting the report is a stale snapshot, not the live data source itself.
Descriptive Statistics: What Your Data Looks Like
Descriptive statistics summarize the data you have, painting a picture of your sample without making guesses about the wider world. It's used for calculating things like average age or max response time.
Business Intelligence (BI) Tools: From Raw Data to Dashboards
BI tools turn raw company data into visual dashboards and reports. They let non-technical teams explore sales trends or user behavior from a data warehouse, but remember: a slick dashboard built on messy data is just a pretty lie.

Data Aggregation: The Big Picture from Small Details
Data aggregation rolls up granular records into high-level summaries, like turning individual sales logs into a daily sales report. It's used to power dashboards and speed up warehouse queries.
Drill-Down Analysis: From Summary to Specifics
Drill-down analysis moves from a high-level data summary to the granular details composing it. It's used in dashboards to investigate a metric's change, like clicking a monthly sales dip to see daily figures.
Cross-Tabulation: Finding Relationships in Your Data
Cross-tabulation reveals how two variables are related by counting their joint occurrences in a grid. It's key for survey analysis or A/B testing. The footgun is assuming correlation implies causation; the table shows a relationship, not its cause.

Ad Hoc Reporting: Answering One-Off Business Questions
Ad hoc reporting is your data "quick dive" for one-off questions, unlike static dashboards. A sales team might use it to see how a holiday affected regional sales.
Data Visualization: Turning Numbers into Insight
Data visualization turns raw data into pictures, revealing stories that numbers alone can't tell. It's used to spot trends, find outliers, and grasp complex relationships in datasets.
Benchmarking: Know Where You Stand in Your Industry
Benchmarking answers "Are we good?" by comparing your performance metrics against industry bests. It's used to set realistic goals for cost, quality, or time. The main footgun is comparing apples to oranges—using benchmarks from dissimilar companies.
Exception Reporting: Focus on Signals, Not Noise
Exception reporting filters out the noise, showing only data that breaks predefined rules. It's used in financial reconciliation to flag mismatched transactions or to alert on system performance dips.
The Semantic Layer: A Business Map for Company Data
A semantic layer is a translation dictionary for data, mapping cryptic database columns to plain business terms like "Revenue." It lets non-technical teams build reports without writing SQL.
Anscombe's Quartet: When Numbers Lie
Anscombe's Quartet shows how four datasets can share identical summary stats (mean, variance) but look completely different when plotted. It's a classic reminder to always visualize your data before trusting numerical summaries.

Chart Selection: Match Purpose, Not Looks
Start with the purpose, not the chart. The question you're asking—'how do these compare?' or 'what's the trend?'—determines the best visualization. A line chart shows trends; a bar chart compares categories.
Gestalt Principles: How Brains Group Visuals
Gestalt principles explain why we see organized patterns, not random dots. Use them in data visualization to group related metrics with proximity or color, guiding users to see the intended story. Ignoring them creates confusing charts that obscure insights.
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