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From “it feels better” to proof: before/after measurement

Contents

Most “it worked” claims prove nothing. Here is how to establish that a correction produced an effect — and how to recognise the cases where no conclusion is possible, which is an answer in itself.

Why “it worked” almost never proves anything

Three months after a visibility project, someone always ends up asking: did it help? The honest answer is often “we don’t know”, and not because the work was poor. It is because nothing was set up to make a conclusion possible.

The problem is structural. Visibility moves on its own: seasonality, an algorithm update, a competitor making a move, someone else’s ad campaign.

Against that moving background, noting that a number went up after a correction demonstrates nothing — it might have gone up without it.

Establishing a link takes three precautions, and all three are taken before, not after.

Precaution 1 — the baseline measurement

Analytics dashboard screen showing session curves and traffic statistics
Photo: Luke Chesser / Unsplash

It is taken before the first change, and it is unrecoverable once the changes have gone through. This is the most common mistake and the most final: you fix first, you think about measuring afterwards, and the prior state no longer exists anywhere.

A good baseline is not a single number taken on a given day. It is an average over a period long enough to absorb the noise — four weeks suits most cases — together with its spread.

Knowing that the number swung between 40 and 60 before the correction changes everything: a value of 65 afterwards is arguable, a value of 120 is not.

What a baseline measurement must contain

  • The period covered, stated plainly, and its length
  • The average value, and the spread between the lowest and highest observed
  • The exact date of the correction, written down in advance
  • What else changed during the period — on your side and in the market
  • The planned observation window, fixed before the result is known

Precaution 2 — one variable at a time

This is the most expensive one to respect, because it contradicts the natural urge to fix everything at once, and because it slows you down. But if you complete the business profile, rewrite three pages and launch a review campaign in the same month, you may well learn that something worked — you will never learn what to repeat for the next client.

When the schedule leaves no room to wait, there is a middle path: space the corrections two to three weeks apart and write down each date. You lose some rigour, you keep a chance of attributing.

Precaution 3 — the observation window

A timeline showing an observation window of several weeks following a correction.
AI-generated illustration

It is set before the result is known — otherwise the temptation is irresistible to stop measuring at the moment the curve looks flattering. Latencies differ a great deal depending on what was corrected.

  • Technical indexing fix: a few days to two weeks
  • Business profile completed or corrected: two to four weeks
  • Bringing directory listings into line: four to eight weeks
  • Review collection restarted: gradual effect, judge over a quarter
  • Content work: a quarter, rarely less
  • Citation by AI assistants: several weeks, read as a frequency and never as yes or no

Choosing the right indicator

A smiling tradesman takes a customer call on his mobile phone in his workshop.
AI-generated illustration

The temptation is to follow the most flattering number — impressions, for instance, which rise easily. Pick instead the indicator closest to the business: calls received, direction requests, forms submitted, quotes requested.

A doubling of impressions with not one extra call is useful information, but mostly it tells you the problem is somewhere else.

Knowing when to conclude “we can’t tell”

That is a legitimate answer, and infinitely more solid than an invented causality.

A consultant who says “the variation is still within the usual noise, we need another month” is more credible than one who attributes every rise to their own work.

4

weeks of baseline measurement, to absorb the noise

1

variable at a time — otherwise you never learn which one acted

0

conclusions available without a measurement taken beforehand

Frequently asked questions

Can you measure if you took no baseline beforehand?

Rarely in a convincing way. Two resources remain: the history kept by your measurement tools, if they were already in place, and a comparison with the equivalent period a year earlier, which partly neutralises seasonality. Both beat nothing; neither replaces a baseline taken on purpose.

How do you tell a real effect from a seasonal swing?

By comparing with the same period a year earlier rather than the previous month, and by checking whether an indicator untouched by the correction moves the same way. If everything rises together, that is the market; if only the targeted indicator moves, attribution becomes defensible.

What if an algorithm update lands during the window?

Write it down and extend the window. A major update makes the period unusable for drawing conclusions — that is not a failure of the method, it is the signal to wait for the background to settle.

Should you measure every week?

Record weekly, conclude quarterly. A weekly reading is there to catch an incident — a sharp drop always has a cause, and it is better handled early. But reading a weekly swing as a trend is commentary on randomness.

Take your starting point before you fix anything

The free audit establishes the current state across eight dimensions and gives you the baseline to compare against in three months. Under 15 minutes, no credit card.

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