Answer:
The reinforcement of a desired behavior on some occasions but not others is called fragmented reinforcement.
Step-by-step explanation:
In the field of psychology, reinforcement is referred as the ability of a stimuli to strengthen the response from a person. Fragmented reinforcement is the ability of a person to respond to a stimulus in a controlled manner. This means that the person can control his/her response to a respective stimuli. For example, a person responds to a headache by taking a pill. Next time when he feels a headache, he might consider taking or not taking the pill according to his wish. Such kind of controlled response is fragmented response.