Can you please give me a simple definition of
used in Data Mining/Intelligence
These are fairly ubiquitous words in and out of the spaces of DM/BI/mining, but confidence can refer to the anticipated range of an output variable given a set of input variable values.
The confidence interval (CI) establishes the range (high sales level +/- CI) within which the corresponding predicted output (i.e., sales) per combination of the inputs (i.e., demographics) occurs 95% of the time. The higher the CI, the less predictive, and therefore useful, the model.
When models are tested against broad real-world company data, the model itself is tested. CIs are used as a key indicator of a model's performance. Confidence intervals can be used to determine which inputs, i.e., combinations of demographic attributes, have the most predictive effect on the outputs, i.e., sales.
At least this is how I've used the term on occasion. This may or may not apply to your situation. If you can provide more context on your situation, that would be helpful.
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