Jerome is training to be a vacuum cleaner sales person. Initially, he got paid for each customer he called on, even if the customer did not ask for a demonstration. Currently, he only gets paid for actually demonstrating the product. Eventually, he will only get paid for actually closing a sale. In this example, Jeromes sales skills are being developed through the use of

According to my research on studies conducted by various psychologists, I can say that based on the information provided within the question Jerome's sales skills are being developed through the use of Shaping. Psychologists refer to this term as a process of reinforcing certain behaviors that help improve a set of desired abilities. Which is what what the company seems to be doing with Jerome in order for him to develop the skills to close more sales.

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