Strength:

Strong     can carry 1 and 1/4 backpacks of stuff, better chance of winning in melee.

Normal   can carry 1 backpack of stuff, normal chance of winning in melee.

Weak       can carry 3/4 of a backpack of stuff, bad chance of winning in melee.

Speed:

Strong     has 7 movements per day, has a good chance to dodge ranged attack

Normal   has 6 movements per day, has a normal chance to dodge ranged attack

Weak       has 5 movements per day, it is a miracle if they dodge a ranged attack

Accuracy:

Strong    searching only costs half a movement, has a good chance to hit with a gun

Normal   searching costs 1 movement always, has an ok chance to hit with a gun

Weak       will find worse stuff searching, it is a miracle if they hit when shooting