I will not use the games played previous season to judge how Manchester City vs arsenal game will be because right now arsenal is a strong team and they have been doing better. I just know Manchester City have more advantage of winning since it is a home game for them, I won't be surprise if Manchester City wins against arsenal but I know the game won't be easy for Manchester City because arsenal is tough. From the performance of arsenal this season I don't think Manchester City will easily defeat them, if Manchester City wins against arsenal that means they are lucky to grab victory.
Most times we do use that at most when we want to place bets of tough games like this, you make good use of head to head to determine the outcome of the next game but in this game, Manchester City are now favorites according to the bookies but they Arsenal would have to say no, we've got this and we want to maintain our position at the top by winning this game.
Take for example the game between Manchester United and Liverpool, who was favorites? Liverpool, Yes? But what happened at the ending of the game? It's football, those players have to go ahead and say " Fuck the bookies" we're winning this game. Mikel Arteta and his lads doing a great job in between.
Both sides indeed have got hard fixtures ahead but Arsenal remains favorite, if they can beat city during the first half of the season, then anything is possible.