Data Science, 2nd Edition

Table 4.4

Golf Dataset With Modified Temperature and Humidity Attributes

No.	Temperature X1	Humidity X2	Outlook X3	Wind X4	Play (Class Label) Y
1	High	Med	Sunny	false	no
2	High	High	Sunny	true	no
3	Low	Low	Rain	true	no
4	Med	High	Sunny	false	no
5	Low	Med	Rain	true	no
6	High	Med	Overcast	false	yes
7	Low	High	Rain	false	yes
8	Low	Med	Rain	false	yes
9	Low	Low	Overcast	true	yes
10	Low	Low	Sunny	false	yes
11	Med	Med	Rain	false	yes
12	Med	Low	Sunny	true	yes
13	Med	High	Overcast	true	yes
14	High	Low	Overcast	false	yes

Step 1: Calculating Prior Probability P(Y)

Prior probability P(Y) is the probability of an outcome. In this example set there are two possible outcomes: Play=yes and Play=no. From Table 4.4, 5 out of 14 records with the “no” ...