"Grappled creatures cannot move and take a –4 penalty to Dexterity."
Escape Artist:" Grapple: You can make an Escape Artist check in place of a combat maneuver check to escape a grapple (see Chapter 8) or to change from a pinned condition to merely grappled."
Escape Artist is obviously a Dex based skill. So is escape artist, used escape a grapple, effected by the -4 penalty?