Assume Bob is at a tennis match where Federer is playing against Nadal. It is Nadal’s match point and all of the sudden Federer states that the ball went out. Bob is Nadal’s true fan and because he thinks Nadal is the best tennis player, and because he really wants Nadal to win, he thinks Nadal’s hit could have not gone out. Therefore he thinks that the hit was on the line. The umpire knows the ball landed on the line because he has true evidence. The Hawk-eye clearly shows that the ball landed right on the line.
Even though both, Bob and the umpire’s beliefs were correct, the umpire’s belief was justified with actual evidence, whereas Bob’s belief was faulty because he had no real proof for his beliefs and his reasoning was subjective.
This being said, the knowledge question “To what extent does subjectivity influence decision making?” arises. In the example above, Bob’s decision was subjective, as he purely decided based on the fact that he is a Nadal fan and because he believed Nadal to a more skilled player than Federer. In this situation Bob had a lucky guess, the fact that he was right this time does not mean he will be correct in other situations. This is because even though Nadal is a very skilled player, all it takes for the ball to go out is the wrong positioning of the racket.
Overall, Bob’s belief was not a justified true belief, even though he may strongly believe it is true. On the other hand, the umpire’s belief was indeed a justified true belief as he had evidence that fully supported his belief. Answering the knowledge question, subjectivity affects decision making to a great extent as every day humans make decisions that are purely subjective and may not always be the best choice, and perhaps the correct decision would be one made through an objective point of view.