I have this book and have made this bear (see a pic of mine in the Whatcha' Knitting forum - topic is labeled FO: Critters). The head on mine came out a little small (he looks a bit more like a mouse than a bear), but here's how I interpreted the instructions you mentioned:
Row 9 is a Purl row, so purl to the end and increase in the last stitch on the row, leaving you with 27 stitches. Then knit 11 rows straight with no increasing (it doesn't say to), which would be rows 10 through 20. Row 20 would be a knit row since odds are purl, evens are knit.
Then on 21 (a purl row), decrease one at the beginning. Now you're back to 26 st. Continue decreasing one st at the beginning of each purl row until you get to row 28 (a knit row). So if you decrease on the odd rows (23, 25, 27) you'd have (25, 24, 23) st on the needle.
Does that make sense? Hope it helps!
P.S. I love this book and have made Robert, Ralph, and a bunch of Snowflakes! Am thinking about Sleepy Sam at some point...