my dog pees in the house

Maybe she's anxious, though about what I have no idea. I don't think it's because she can't find the potty. We take her out to pee several times a day, and when we leave her alone in the house, she never pees on the carpet. When she does do it, and she's sometimes done this when we're not around, sometimes when we're looking right at her, it seems like she does it on purpose, with something in mind.

The closest explanation I can think of is that she gets really excited about something and that's how she reacts.

Ripley's never peed the bed, thank goodness.