You walk up to a soda machine and put in a dollar, and are rewarded with a bottle of root beer. when you put in another dollar, you get another soda. assuming that the machine has a limitless supply of root beer, which kind of reinforcement schedule does this machine operate on?

This would be continuous reinforcement.

Explanation:

As the name states, the behavior will be reinforced every time it takes place. By placing the dollar in the machine, you get a root beer and since every time you place a dollar you get a bottle, this will make you want to put more dollars in in order to get more, thus reinforcing this behavior.

This is the same example as Skinner's box in which a rat pulls a plank and gets a pellet every time it does this.

Continuous reinforcement schedule

Explanation:

First, there are two different types of reinforcement:

The positive reinforcement applies a stimulus to increase the frequency of the desirable variable. The negative reinforcement removes a stimulus to increase the frequency of the desirable variable.

In this example, you are getting a positive reinforcement because you are getting a root beer as a reward.

However, the positive reinforcement divides itself in different types:

A continuous reinforcement schedule gives us a reinforcement every time we engaged in the desired conduct.

On the other side, the partial reinforcement schedule gives us a reinforcement after a fixed (or not fixed) amount of desired conducts.

In this case, the machine has a limitless supply of root beer so it will give you a can EVERY TIME you put in a dollar in the machine.

Therefore, we are talking about a continuous reinforcement schedule.