My TI-83 Plus: the lists under Stat Edit begin with L2 (and go to L6). There is no L1. Which hasn't previously been a problem, as I can enter data into L2, etc. But now I'm trying to do simple linear regression, which (according to instructions in stat book for using TI), requires x-data in L1, y-data in L2. But I thought it would read data from the first two lists with data, so whether they were L1, L2, or whatever, should not matter. Apparently not. I can't get it to do simple lin regression, apparently because it's looking for data in L1, but there is no L1! Is there a way to get it to look in L2 and L3?
Or, what happened to my L1, and how do I get it back?