Even if you are being robbed if you stab someone with a knife you would be going to jail. If someone tries to rob you with a gun give them the ps4, if someone tries to rob you with a knife, give them the ps4, if someone tries to rob you with nothing in hand then it would be your choice to either run or give it to them. If you are 16 those are your only options.
I'm 16, so all I have is a big-**bleep** 7-inch Knife. ;P
Haha, then I won't Brandish it. ;P
If I knew you in real life, I'd let you bring my Panther.
When carrying a blade it's important to understand that you can easily be disarmed and it can end up being used against you. Since a steak knife is not meant for combat, your agressor will assume you have no idea what you are doing and take it from you.
If you're only 16 your best bet is to bring a friend with you, or better yet, an adult. And for god's sake, if you must carry a weapon, carry mace, or make sure it's an inconspicous blunt object. When I was 14 I once used my skateboard as a weapon against a guy who pulled a knife on me.