Descriptive, Diagnostic, Predictive, Prescriptive
The four questions analytics can answer
Analytics maturity runs from descriptive (what happened) to diagnostic (why) to predictive (what will) to prescriptive (what should we do). Each level needs different methods and earns a different conversation.
What you will learn
- Place any analysis in one of the four maturity levels
- Match methods to maturity level
- Sequence work so prescriptive advice rests on trustworthy description
What is this?
Analytics answers four escalating questions. Descriptive: what happened? Diagnostic: why did it happen? Predictive: what will happen next? Prescriptive: what should we do about it? Each level builds on the previous one, and each requires different data, methods and governance — you cannot prescribe before you can describe reliably.
Why do you need it?
- Teams over-invest in prediction while their description is still broken.
- Mixing levels confuses expectations ('is this dashboard or is this a recommendation?').
- Each level implies different stakes and different rigor requirements.
- Knowing the ladder tells you where your team's analytics actually is.
Mental model
A doctor's visit
Analytics levels
First symptoms are recorded (descriptive), tests explain them (diagnostic), prognosis forecasts (predictive), and the treatment plan is chosen (prescriptive). Skipping the diagnosis to prescribe is malpractice in both worlds.
How it works
- Descriptive: dashboards and reports compute counts, rates and trends from historical data.
- Diagnostic: drill-downs, segmentation and correlation identify drivers of an observed pattern.
- Predictive: regression, time-series forecasting and classification models estimate future values.
- Prescriptive: optimization, simulation and recommendation logic choose actions that maximize an objective.
- Feedback: measuring outcomes of prescriptions closes the loop and improves the whole ladder.
The analytics maturity ladder.
In production
- A descriptive BI layer reports weekly revenue; diagnostic analysis ties a dip to a pricing change in one region.
- A predictive model forecasts demand weekly so the supply chain pre-orders stock.
- A prescriptive optimization recommends which customers should receive a retention offer, using LTV and predicted churn.
Best practices
- Validate each level before climbing: a predictive model built on skewed descriptions misleads.
- Label deliverables by level so stakeholders know whether this is a report or a recommendation.
- For prescriptive advice, state the objective function and constraints explicitly.
- Timebox prediction to far-future assumptions you document.
Common mistakes
- Calling a descriptive dashboard 'AI' — it is not predictive.
- Going straight to prediction when the diagnostic story is still a mystery.
- Prescribing actions with no measurement plan, so nobody learns if it worked.
- Overfitting the past and presenting it as a forecast of the future.
Debugging tips
- Open 'predictive' deliverables and check for a historical description underneath — it often is.
- When prescriptions fail, check the descriptive input they were built on.
- Revalidate forecasts against actuals with error metrics (MAE, MAPE), not vibes.
- Segment predictions to find where the model is confident vs guessing.
Interview checkpoint
Quick quiz
'Sales declined 12% this quarter, driven by churn in enterprise accounts.' Which level is this?
Prescriptive analytics requires no prediction layer underneath.