Setting up a vector of parameters

I'm working on solving a system of differential equations and I'm having trouble setting up a vector of parameters. This is the code for one of my model files:

function dy1dt=LogisticsModel(t,y1,param1)
r1=param1(1);
k1=param1(2);
dy1dt=r1*y1*(1-(y1/k1));

This is the code for the other:

function dy2dt=LogisticsModel2(t,y2,param2)
r2=param2(1);
k2=param2(2);
dy2dt=r2*y2*(1-(y2/k2));

Basically, I just want a vector, param, containing r1, k1, r2, k2. Whenever I try to set it up like

r1=param(1);
k1=param(2);
r2=param(3);
k2=param(4);

I get error messages. I've tried several different methods to do this and I can't figure it out. Please help.