[chasd00]

> ADP say that they handle payroll for one in six of all companies in America

that's less than 20%. If you had 10 people to interview and interviewed 2 of them i wouldn't say you interviewed a representative sample of the 10.

[IshKebab]

No, but if I had 1000 people to interview and interviewed 200 of them at random then absolutely yes.

I know right. Statistics.

[protonbob]

The key is "at random". Businesses are not randomly assigned to use ADP

[IshKebab]

That's a separate problem. I have no idea what the sampling bias is, but the issue isn't that they "only" sample 20% of the population.