An internet service provider (ISP) has randomly selected a sample of 223 observations concerning values of the response variable Churn and several predictor variables based on customer activity during the most recently billed month. Here Churn equals Yes if a customer churned-left the internet service provider for another ISP-and equals No otherwise. The predictor variable MinutesOn is the average daily minutes the customer spent online. EmailSent is the average daily number of emails the customer sent from the email address provided by the ISP. ServCalls is the number of times the customer called for service. Below is part of the classification tree they derived from the data collected in the study. Assume they classify those with a churn probability estimate (based on the sample proportion) of at least .5 as churners. Based on this classification tree, a member of the study sample who spent an average of 327 minutes online per day, sent an average of 4 emails per day from their ISP-provided email address, placed no service calls, and churned would be
A) inaccurately classified as a churner.
B) inaccurately classified as a non-churner.
C) accurately classified as a churner.
D) accurately classified as a non-churner.

Question

An internet service provider (ISP) has randomly selected a sample of 223 observations concerning values of the response variable Churn and several predictor variables based on customer activity during the most recently billed month. Here Churn equals Yes if a customer churned-left the internet service provider for another ISP-and equals No otherwise. The predictor variable MinutesOn is the average daily minutes the customer spent online. EmailSent is the average daily number of emails the customer sent from the email address provided by the ISP. ServCalls is the number of times the customer called for service. Below is part of the classification tree they derived from the data collected in the study.  Assume they classify those with a churn probability estimate (based on the sample proportion) of at least .5 as churners. Based on this classification tree, a member of the study sample who spent an average of 327 minutes online per day, sent an average of 4 emails per day from their ISP-provided email address, placed no service calls, and churned would be
A) inaccurately classified as a churner. 
B) inaccurately classified as a non-churner. 
C) accurately classified as a churner. 
D) accurately classified as a non-churner.

Quizplus · Accepted Answer

This customer would have MinutesOn < 511 and ServCalls < 3. (Their average number of emails would not be relevant in this case.) The 192 customers with MinutesOn < 511 and ServCalls < 3 would be classified as non-churners because only 15 were churners for a churner proportion of 15/192 = .078. However, since the specific customer being considered did churn, the non-churner classification for them would be inaccurate.

An Internet Service Provider (ISP) Has Randomly Selected a Sample