Spreadsheet regression or a dedicated analysis tool for a 1,200-person company?

I chose the tool at 1,500 people and do not regret it, but not for the regression. What I use daily is the remediation modelling: it tells me the cheapest set of adjustments that brings the gap under a threshold, and lets me test an offer or promotion against the model before it is made. Doing that by hand for 80 offers a year was not realistic.

I have done both, in that order. The scripted route took about six weeks of evenings, plus two days of a statistician's time to review the model. After that a rerun took minutes. Weakness: it lived in my head, and when I was off sick for a month nobody could run it.

We bought a tool when we passed 2,000 employees and needed HR business partners to check individual cases themselves. If you are the only user, you are paying 28,000 for an interface for one person.

My suggestion: script it, document it properly, have it reviewed externally, and revisit when someone other than you needs to use it.

Whichever you choose, ask where the data sits. Our information security team took three months to approve sending individual pay with gender and ethnicity to an external platform, and wanted it hosted in the EU. That delay was longer than the implementation.

Decision made: scripted model with an external review, and a written runbook so it is not just me. I had not weighed the single-user point properly. I will come back in a year and say whether I held my nerve.