Your respect is made up of the following factors:

Running Respect (see below): 40%
Mission Progress: 36%
Territory Under Control: 6%
Money: 6%
Fitness: 4%
Clothes: 4%
Girlfriend Progress: 4%

Your Running Respect is changed by the following factors:

Territory gained: +30%
Killing a gang member: +.5%
Killing a dealer: +.005%
Killing a member of your gang: -.005%
A member of your gang is killed: -2%
Territory lost: -3%

Your respect affects the number of gang members that you can recruit:

Above 1%: 2
Above 10%: 3
Above 20%: 4
Above 40%: 5
Above 60%: 6
Above 80%: 7