I'm conducting a study of television audience behavior. I have descriptions of program titles and a list of program categories. I have two graduate...

I'm conducting a study of television audience behavior.  I have descriptions of program titles and a list of program categories.  I have two graduate assistants helping me. I ask them to each code the same sample of 20 programs.  The two graduate assistants code 85 percent of the programs the same--meaning they put them in the same categories. From this I can say the measure is:

Reliable

Valid

Neither reliable nor valid

Because I didn't give the coders enough to work with, I can't tell whether the measure is reliable or valid.

Statistically significant