I realized when I got home that I have this book, so I took a look.
The sweater is knit from side to side rather than bottom to top, so you would work the front the same as the back up to a certain point. The back will measure a total of 9 1/2 inches from the beginning, while the front will end up measuing 4 1/2 inches from the beginning. These measurements end up being side to side when you hold the sweater as it is worn.
"Trust the pattern!"
Time flies like an arrow, but fruit flies like a banana.
Hop aboard while we follow the cloud-covered van of knitting harmony, man!! Woooo!! --Hedgehog
IngridKH on Ravelry