What influenced starting weapons?

[Rex is back, baby!]

At the start of the game you are unarmed until you open a chest with a random assortment of weapons.

I know one way to control which weapon you get is through the weapon focus feat, but what else influences it? Class?

[.Blade.]

I think it's just weapon proficiency, something more explicit like "Dueling Sword" proficiency e.g will make a dueling sword show up in the chest 100% of the time but if I were to guess something like "Martial" or "Simple" give an assortment of weapons that fit into that category but also are determined by some loot table.