Question

A statistical model was developed to predict whether passengers on the Titanic ship survived based on their information such as age, number of siblings and spouses were on the ship, sex, the fare, class. The table below presents the predicted results you get from the model compared with the actual record:

	Predicted survived	Predicted not survived
Actually survived	2245	280
Actually not survived	157	1137

a. If picking a random passenger, what is the probability that the passenger survived according to the model?

b. If picking a random passenger, what is the probability that the passenger did not survive according to the real record?

c. If a passenger was predicted as a survivor, what is the probability that the passenger actually survived according to the actual record?

d. If a passenger was predicted as a non-survivor, what is the probability that the passenger actually did not survive according to the actual record?

Answer 1

a. If picking a random passenger, the probability that the passenger survived according to the model

=(2245+157)/(2245+2245+157+1137)=0.4153.

b. If picking a random passenger, the probability that the passenger did not survive according to the real record

=(2245+280)/(2245+2245+157+1137)=0.4365

c. If a passenger was predicted as a survivor, the probability that the passenger actually survived according to the actual record=2245/(2245+157)=0.9346

d. If a passenger was predicted as a non-survivor, the probability that the passenger actually did not survive according to the actual record=1137/(280+1137)=0.8024