How do group incentives influence the behaviors of the physicians?

Sakal, who graduated from medical school five years ago, has just completed a residency and fellowship in radiology and joined a five-member group in the Southwest United States. He is eager to do a good job and started out by putting in long hours at two of the hospitals that his group covers. His salary is based on his group’s overall billings, but as a junior partner he receives his share minus 20 percent to buy into the group.
He was excited to become a radiologist, as the average salary of a radiologist in the United States is just over $500,000. The group he joined is well trained, and the other four radiologists have been working in the field for 5–15 years.
Things were going well until Sakal’s extended family suffered financial setbacks and he realized that he is not making enough money to cover all his obligations. He has about $300,000 in student debt from his medical education and his parents now have severe health problems and no health insurance.
They are both incurring substantial hospital bills, and will continue to in the foreseeable future. Sakal comes from a culture that deeply honors parents and he would do anything to help them. It would violate everything he believes in to do otherwise. He estimates that he needs to earn at least another $100,000 per year to be able to cover these obligations.
He considers working longer hours, but under the revenue-sharing arrangement his group would receive most of the money. In addition, two of the radiologists have already cautioned him about spending so much time in the reading room, because it made them look bad. Sakal decides to go to the head of the radiology group and ask if there might be a way to increase his income.