# I Is there a term for this type of unknown experimental interference?

#### .Scott

Homework Helper
Summary
Term for unknown alternate causes in experiments.
You collect 200 data points, 100 with input $A$ and 100 with input $A'$.
For all 100 $A$ you get output $C$ and for all 100 $A'$ you get $C'$.
That's way more than 5 standard deviations, so you're ready to publish...

But not really.

Because what matters is not just that input $A$ is well-correlated to $C$ but that there is no $B$ that is also correlated to $C$.
In the simplest (and probably worse) case, we may have collected all of the results from $A$ before any of the results from $A'$ - so there was a particular time when $C$ outputs ended and $C'$ outputs started. That would create many potential $B$s: Room temperature or humidity were rising or falling; the experimenter was getting tired or more practiced; the apparatus broke or was wearing out.

So you are not ready to tout your 5 standard deviations until you run the experiment in a manner that reduces the likelihood that there could be such an unknown alternate cause. Is there a common (or otherwise better) term for such "unknown alternate causes"?

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#### Dale

Mentor
Maybe "confounders"

#### .Scott

Homework Helper
Maybe "confounders"
Yes, excellent! And I had run into that term before.
Thanks!

"Is there a term for this type of unknown experimental interference?"

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