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How to Be a Top-Notch Data Analyst / Module 09

Communicating the answer

Six lessons, about an hour. Every technique from modules 1–8 is wasted if the answer doesn't land — this module is about making sure it does.

Module 9 worksheets Real templates for the three deliverables this module builds toward — a one-sentence finding worksheet, a chart-choice decision tree, an executive summary structure, and a hedged-number phrasebook. One .docx, five pages.
Lesson 9.110 minutes

The one-sentence finding, written before the chart exists

Write the sentence first: "Ibadan Central's revenue fell 14% in August, driven mostly by three fewer trading days after a generator fault." Only once that sentence exists do you build the chart, the slide, or the dashboard designed to make that exact sentence obvious at a glance.

Build the chart first, and you'll spend twenty minutes reverse-engineering what point it's supposedly making. Write the sentence first, and the chart becomes a much smaller, much clearer design problem: "what visual makes this specific claim visible in two seconds."

Keep this
  • Write the one-sentence finding before touching a chart tool — the sentence should drive the chart, never the reverse.
  • If you can't write the sentence yet, you don't have a finding yet — you have data still waiting to become one.
Lesson 9.211 minutes

Charts that argue: choosing a form that carries the point

A chart type is an argument, not a decoration. Choosing the wrong one makes true data look like it's arguing something else.

Comparing categoriesBar chart — Chidi can see which branch is biggest without reading a single label.
Showing change over timeLine chart — the shape of the trend is the point, not any single value on it.
Showing compositionStacked bar, used sparingly — a pie chart with more than four slices argues nothing clearly.
Showing a single headline numberA big number with a comparison, not a chart at all — sometimes the honest visual is no visual.

A dual-axis chart, a 3D pie chart, or a chart with fourteen colours is rarely clarifying — it's usually a sign the underlying finding hasn't actually been simplified to one sentence yet.

Keep this
  • Match the chart type to the kind of claim — comparison, trend, composition, or headline — deliberately, not by habit.
  • A chart that needs a long caption to explain what it's showing has usually chosen the wrong form.
Lesson 9.310 minutes

Structuring an executive summary people finish reading

Chidi reads the first two sentences of anything you send him, and decides in that time whether the rest is worth his attention. Structure accordingly: finding first, then the one piece of supporting evidence that matters most, then anything else — never build up to the finding at the end.

Backwards versus forwards
Buried finding

"I looked at August sales across all nine branches, broke it down by category and by week, and after controlling for seasonality and comparing against last year..." — the actual finding arrives in paragraph four, if Chidi is still reading.

Finding first

"Ibadan Central's revenue fell 14% in August — mostly explained by three lost trading days after a generator fault, not a real demand problem. Details below if useful."

Keep this
  • Lead with the finding, always — never make Chidi read to the end to find out what you actually discovered.
  • Everything after the first two sentences should be there because Chidi wants more, not because you needed to build up to it.
Lesson 9.410 minutes

Presenting a number you are not fully certain about

Module 5's statistics discipline showed you how to know when you're not fully certain. This lesson is about saying so out loud without it sounding like you don't know what you're doing.

Hedging that reads as competence, not weakness

"Revenue is roughly flat month-on-month — within the range Lekki normally moves week to week, so I wouldn't read this as a real trend yet. I'll have a clearer read after another two weeks of data."

This states the number, states the honest uncertainty, and states exactly what would resolve it — which reads as more competent, not less, than a false-confident single figure that later turns out wrong.

Keep this
  • State uncertainty plainly and specifically — what's uncertain, and what would resolve it — rather than hiding it or over-hedging vaguely.
  • Honest uncertainty, stated clearly, builds more trust over time than false confidence that occasionally turns out wrong.
Lesson 9.510 minutes

Handling "that doesn't look right" in the room

Module 6.7 covered this for a dashboard specifically; the same discipline applies live, in a meeting, when Chidi or a branch manager pushes back on a number you're presenting in real time.

The live version of the verification sequence

"That's useful pushback — can you say what number you were expecting? ... Okay, let me check whether we're looking at the same date range first, because that's the most common reason these disagree. [checks] You're right, I had July, you meant the rolling twelve months — let me pull that specific number now / I'll have it to you by end of day."

Never defend a number reflexively in the room before actually checking it. Never capitulate and agree it's wrong before checking either. The credible move, every time, is visible verification — even if it takes an extra minute of silence while you check.

Keep this
  • Neither defend nor concede immediately when challenged live — verify visibly, out loud, before answering either way.
  • A calm "let me check" is more credible in the moment than an instant answer in either direction.
Lesson 9.69 minutes

Saying no, and offering the smaller question you can answer

Sometimes the honest answer is "I can't answer that with what we have" — and the module 1 scoping habit applies here in reverse: rather than a flat no, offer the smaller, real question that the same data actually can answer.

A "no" that's actually useful

Chidi asks: "Would opening a tenth branch in Ikorodu definitely be profitable?" You: "I can't give you a definite answer from our data alone — that needs a market study we don't have. What I can tell you: based on our existing branches' revenue-per-square-metre and how similar-density areas perform, here's a realistic range. That's a real input, not a full answer."

Keep this
  • A flat "I can't answer that" is a dead end. Naming the smaller, real question the data can answer keeps the conversation useful.
  • Being honest about a question's limits is not the same as being unhelpful about it.
Before the drill

Have your module 6 dashboard findings or module 5 drill results handy — you'll be turning one real analysis into three different deliverables.

Module 9 drillabout 75 minutes

One analysis, three deliverables

Take any real finding from earlier in this course — Ibadan Central's August dip, the Lekki promotions fan-out, or one of your own drill results — and produce it three ways.

  1. A Slack message to Chidi. Two sentences, finding first, appropriately hedged if the certainty warrants it.
  2. A one-page memo. Finding, evidence, what you're not certain about, what you'd recommend.
  3. Three slides for a board meeting. One chart chosen deliberately per lesson 9.2, minimal text, built to survive being challenged live per lesson 9.5.

Same underlying finding, three genuinely different artifacts — not the same paragraph reformatted three times.

What this drill is really testing

Whether you can adjust register and depth for three different real audiences without losing the honesty or the certainty-hedging that modules 5 and 9 have built — a Slack message that's too formal, or slides with too much text, both fail this just as much as an inaccurate number would.

Before module 10

Module 10 turns to running yourself as an analyst long-term — documentation, request queues, and building a portfolio from work like this drill's.