Assignment Help - Statistics

1. What is the overall error rate based on the confusion matrix? A) 0.28

B) 0.38 C) 0.21 D) 0.17 E) 0.10

2. What proportion of the passengers did not survive the Titanic sinking? A) 0.28

B) 0.10 C) 0.20 D) 0.62 E) 0.38

3. What is the chi-squared test statistic value for H0: B1 = 0 versus Ha: B1 ≠ 0? A) -3.44

B) 11.81 C) 3.44 D) -1.85 E) 0.0006

4. The point estimate for B4 is b4 = -0.03. What is the estimated standard deviation of b4? A) 7.06

B) 2.66 C) 0.03 D) 0.01 E) Cannot be determined.

5. What is the predicted probability of survival for a passenger with Pclass = “Middle”, Sex = “female”, Age = 30? A) 0.80

B) 0.20 C) 0.65 D) 0.35 E) 0.62

6. What are the odds for not surviving for a passenger with Pclass = “Upper”, Sex = “male”, Age = 50?

A) 0.33 B) 0.69 C) 2.05 D) 0.49 E) 1.00

7. Consider the following two passengers: Passenger 1 has the following data: Pclass = “Middle”, Sex = “male”, and Age = 50, and Passenger 2 has the following data: Pclass = “Lower”, Sex = “male”, and Age = 50. Let odds1 = odds of survival for passenger 1. Let odds2 = odds of survival for passenger 2. What is the relationship between odds1 and odds2? The symbol × represents multiplication.

A) odds1 ≈ 4.11 + odds2 B) odds1 ≈ 0.41 + odds2 C) odds1 ≈ 1.95 × odds2 D) odds1 ≈ 0.51 × odds2 E) odds1 ≈ 0.41 × odds2

8. For a female passenger in Pclass = “Upper”, by how much does the odds for surviving change when age goes up by 10 years?

A) The odds for survival go up by a multiplicative factor of about 1.01. B) The odds for survival go up by a multiplicative factor of about 1.11. C) The odds for survival go down by a multiplicative factor of about 0.99. D) The odds for survival go down by a multiplicative factor of about 0.91. E) The odds for survival go up by a multiplicative factor of about 11.

9. A red arrow on the ROC graph points to a specific coordinate (FPR = 0.20, and TPR = 0.80) on the plot. If we were to back out the probability threshold corresponding to this point and recompute the confusion matrix, what overall error rate would we get?

A) 0.12 B) 0.10 C) 0.15 D) Cannot be determined. E) 0.20