AI for Data & Analysis

45 min intermediate Lesson 5

Learning Outcomes

  • Prepare a dataset so AI can read it accurately
  • Interpret patterns, totals, and outliers in raw numbers through conversation
  • Generate working spreadsheet formulas from a plain-English description
  • Summarise a table of figures into an executive-ready narrative
  • Validate AI-generated analysis before you rely on it

Lesson Plan

Segment Duration Topic
Intro 3 min Why data work no longer needs a spreadsheet wizard
Prepare 6 min Getting data into an AI-readable shape
Interpret 8 min Asking AI what the numbers say
Formulas 8 min Generating formulas from plain English
Trends & outliers 8 min Spotting movement, flags, and anomalies
Summarise 6 min Turning a table into an executive narrative
Validate 4 min Checking AI's maths before you trust it
Wrap-up 2 min Key takeaways, preview next lesson

Before You Begin

Pre-work:

Shopping List:

  • Any AI assistant open in your web browser (the free tier is fine)
  • One dataset of 10–200 rows you understand well enough to sanity-check
  • A spreadsheet app (Excel, Google Sheets, or similar) to paste formulas into

1 Get Your Data Into a Shape AI Can Read

AI reads text, not spreadsheet cells. To hand over a small table, copy the rows and paste them into the chat — most assistants read tab- or comma-separated data instantly, and many let you upload the file directly.

Before you paste, tidy the data: one clear header row, one record per row, no blank rows or merged cells, no colour-coding that carries meaning (AI can't see colour), and a quick note on any cryptic column name. Then frame the paste with context:

> Here is monthly sales data for our four regions. Each row is one
> month. "Units" is items sold, "Revenue" is in GBP. Read it and
> tell me back in one sentence what this table contains.
>
> Month  Region  Units  Revenue
> Jan    North   420    18900
> Jan    South   380    17100
> ...

That last instruction — tell me back what you see — is cheap insurance against a misread column.

TIP
State the units
If a column holds money, dates, or percentages, say so. Revenue is in GBP or Date is DD/MM/YYYY stops the AI misreading 03/04 as the wrong month or treating text as a number.
WARNING
Confidentiality first
Before pasting, ask: would I email this outside my team? If it holds customer names, salaries, or anything regulated, anonymise it or use an approved enterprise tool. Lesson 10 covers governance in full.

2 Ask the Data to Explain Itself

Once the AI confirms it has read your table correctly, start broad before you drill in:

> Based on the table above:
> 1. Which region had the highest total revenue this year?
> 2. Which month was strongest overall, across all regions?
> 3. What's the average revenue per region per month?
> Show the key numbers you used so I can follow your reasoning.

Asking the AI to show the numbers it used is the most useful habit in this lesson — it turns a black-box answer into something you can check.

You can layer follow-ups without re-pasting — the AI remembers the table within the conversation. Mix question styles: orienting ("summarise this in plain English"), pointed ("which row is highest?"), comparative ("how does Q1 compare to Q2?"), and diagnostic ("why might South be lagging?").

NOTE
Reasoning, not facts
Diagnostic questions like 'why might South be lagging?' produce educated guesses. The AI sees your numbers, not your market — treat its 'why' answers as things to check, never as conclusions.

3 Generate Formulas From Plain English

This is where hours come back to your week. Instead of remembering spreadsheet syntax, describe what you want in words and let the AI write the formula — then paste it in and adjust the references.

> In Google Sheets, I have months in column A, region in column B,
> and revenue in column D. Write a formula that totals revenue for
> the "North" region only. Explain what each part does.

A good assistant returns the formula plus a short explanation — a SUMIF that adds column D where column B equals "North". Read the explanation; it's how you learn to trust or correct the result. The same pattern handles counting rows, looking up a value, or month-on-month percentage change — just describe the goal.

If a formula errors when you paste it, hand the error back:

> That formula gives a #REF! error in Excel. My data runs from row 2
> to row 47. Fix it and tell me what was wrong.
TIP
Name your app and test small
Say in Excel or in Google Sheets — they differ in small ways — to get a formula that works first time. Then check it against three rows by hand before applying it to thousands: 'almost right' across 5,000 rows is worse than no formula at all.

4 Spot Trends, Outliers, and Anomalies

AI is good at noticing what stands out — the spike, the dip, the row that doesn't fit. But you must define what "unusual" means, or it'll guess.

> Look at the monthly revenue for each region. Point out:
> - Any month more than 20% above or below that region's average
> - The overall trend for each region: rising, flat, or falling
> - Anything that looks like a possible data-entry error
> List each finding with the region, the month, and the figure.

The prompt gives a concrete rule (20% from average) instead of the vague word "outlier." For trends, ask the AI to characterise direction and pace — "describe the trend in two sentences: is growth speeding up, slowing, or steady?" — not predict the future.

NOTE
Describe, don't predict
Asking AI to describe what already happened is reliable; asking it to forecast next quarter is far riskier — it has no knowledge of your pipeline or market. And a flagged 'possible error' means 'worth a look,' not 'this is wrong': a record-breaking month and a typo look identical to AI. You decide which it is.

5 Turn the Table Into an Executive Narrative

A table of numbers rarely lands in a meeting; a short, plain-English story does. Ask the AI to translate it for a specific reader.

> Summarise this sales data for our leadership team in four bullet
> points an executive can act on. Lead with the headline number,
> name the strongest and weakest regions, and end with one
> recommendation. No jargon. Round figures to the nearest thousand.

The same data can be retold for different readers — "headline number first, no jargon" for leadership, "exact figures, variance vs budget" for finance, or "neutral, one paragraph" for a board pack.

TIP
Lead with the number, end with the 'so what'
'Revenue rose 12%, so we should reinvest in the North team' beats a summary that restates the table. And read the draft aloud: if it doesn't sound like you, ask it to rewrite in a more direct, confident tone, then edit the wording yourself.

6 Validate Before You Trust

People skip this step and later regret it. AI does arithmetic, but it can also state a wrong total with full confidence. Catch it with a three-check routine:

  1. Spot-check one number in the spreadsheet. If it checks out, trust the rest.
  2. Sanity-check the scale. "£4.2 million" when you sell a few hundred units a month is a red flag.
  3. Re-derive it — make the AI show its working a second way:
> You said total revenue was 312,400. Recalculate it by adding the
> four regional totals separately, then show those four numbers and
> the new sum. Do they match your earlier figure?

If the two numbers disagree, you've found a problem before it cost anything. Common risks and their quick checks:

Risk How to catch it
Silent arithmetic error Spot-check one figure by hand
Misread column Ask "which column did you treat as revenue?"
Made-up data point Confirm every figure traces back to your table
Overconfident "why" Treat all causes as hypotheses to verify
WARNING
You own the output
The moment you paste an AI figure into a report with your name on it, it's your number. Validation isn't optional caution — it's the price of using AI responsibly. See [Lesson 10: AI Ethics & Limitations](/courses/02-practical-ai/lesson-10/) for the fuller picture.

Questions & Answers

Q: My spreadsheet has 5,000 rows. Can I just paste all of it?
Often not in one go — large pastes can exceed what the chat accepts or hurt accuracy. For big datasets, upload the file (if supported), or have the AI write formulas and paste only the summarised results back. Raw pasting works best for tables of a few hundred rows or fewer.
Q: How do I know the AI didn't just invent a number that looks plausible?
You don't, until you check — that's why Step 6 exists. Spot-check one figure by hand and ask the AI to show the rows behind any total. If a number can't be traced back to data you provided, treat it as suspect.
Q: Is it safe to upload our actual company financials?
It depends on your tool and policy. Consumer free tiers may use inputs to improve their models; enterprise tiers usually do not. When in doubt, anonymise (swap real names and figures for proxies) or get explicit sign-off. Lesson 10 covers data classification properly.
Q: Can AI replace my analyst or finance partner?
No — it speeds up the routine parts (summarising, formula-writing, first-pass pattern spotting) so humans can focus on judgement and decisions. AI doesn't know your strategy or why last March was unusual. Use it for the legwork, not the call. And when a formula errors, paste the exact message back with your app name — it's usually a quick fix once the AI can see it.

Key Takeaways

  1. Prep beats power. A clean table with clear headers and stated units beats the cleverest prompt on messy data.
  2. Make the AI show its working. Revealing the numbers behind every answer turns a guess you can't check into one you can.
  3. Describe what you want, not how. Plain-English requests produce working formulas — AI handles syntax, you handle intent.
  4. Define "unusual" yourself. Concrete rules ("more than 20% from average") give reproducible findings; vague words give vague answers.
  5. Translate numbers into a story. Data retold for the right audience with a clear "so what" is what moves a meeting.
  6. Validate before you trust. Spot-check, sanity-check, re-derive. In your report, the number is yours.

Next Steps: Lesson 6: AI for Project Management