Machine Learning and Weka Interview (5 Questions)

Q1:
Topic: Naïve Bayes Classifier

A patient goes to see a doctor. The doctor performs a test with 99% reliability - that is, 99% of people who are sick test positive and 99% of the healthy people test negative. The doctor knows that only 1 percent of the people in the country are sick. Now the question is: if the test comes out positive, is the probability of the patient actually being sick 99%?

Q2:
Topic: Naïve Bayes Classifier

We have two classes: “spam” and “ham” (not spam).

Training Data:

Class: Ham
D1: “good.”
D2: “very good.”

Class: Spam 
D3: “bad.”
D4: “very bad.”
D5: “very bad, very bad.”

Test Data:
Identify the class for the following document:
D6: “good? bad! very bad!”

Q3:
Topic: Apriori Algorithm

TID : items_bought
T1 : { M,O,N,K,E,Y } 
T2 : { D,O,N,K,E,Y }
T3 : { M,A,K,E }
T4 : { M,U,C,K,Y }
T5 : { C,O,O,K,I,E }

Let minimum support = 60%
And minimum confidence = 80%
Find all frequent item sets using Apriori.


Q4:
Topic: Decision Tree Induction

Create the decision tree for the following data:

Outlook,Temperature,Humidity,Wind,Play Tennis
Sunny,Hot,High,Weak,No
Sunny,Hot,High,Strong,No
Overcast,Hot,High,Weak,Yes
Rain,Mild,High,Weak,Yes
Rain,Cool,Normal,Weak,Yes
Rain,Cool,Normal,Strong,No
Overcast,Cool,Normal,Strong,Yes
Sunny,Mild,High,Weak,No
Sunny,Cool,Normal,Weak,Yes
Rain,Mild,Normal,Weak,Yes
Sunny,Mild,Normal,Strong,Yes
Overcast,Mild,High,Strong,Yes
Overcast,Hot,Normal,Weak,Yes
Rain,Mild,High,Strong,No

Q5:
For Iris Flower dataset, show the correlation plots for each pair of attributes.

Iris dataset comes in ARFF format alongside Weka tool.

Tags: Machine Learning,Weka,Technology,