Basic Statistics for Economics — DU B.A (Prog.) Economics as Major Previous Year Question Papers

1. For the following data Rating Frequency Very good 521 (a) Construct a frequency distribution. (b) Construct a percent frequency distribution. (c) Construct a bar chart for the percent frequency distribution. (5+5+5) 2. (a) Consider a sample with data Compute Range, Interquartile range, Variance, Standard deviation. (b) What is Sampling? What are the different sampling techniques? (5) (a) Compute P(A ∩ C) and P(B ∩ C) (b) Find P(A/C) and P(B/C) (4) (c) Are the two events A and B mutually exclusive? Explain. (2) 4. The following are the responses for the question- Does global warming pose a threat during your lifetime? Responses Age On the basis of this information answer : (a) (b) What is the probability that a respondent 18-29 years of age thinks that global warming will not pose a threat during his/her lifetime? (5) For a randomly selected respondent, what is the probability that a respondent answer is yes? (5) 6. (a) (b) Compute the probability of randomly drawing five cards from a deck of 52 cards and getting exactly one ace. (5) Five boys and five girls have to be seated in a row. Find the probability that two particular boys are always together. (5) Section – III 7. (a) The probability of a man hitting a target is ¼. If he fires 3 times, what is the probability of his hitting the target at least once. (5) (b) Consider a binomial experiment with n=20 and p=0.7, find P (x≥16), 8. The mean cost of domestic airfare is rupees 385 per ticket, assuming that the airfares are domestically distributed with a standard deviation of Rs. 110 (a) What is the probability that the domestic airfare is Rs., 550 or more? (b) What is the probability that the domestic airfare is between Rs. 300 and 9. The following table shows the monthly demand for a product Unit demand Probability (a) If the firm bases monthly orders on the expected value of monthly demand, what should be the firm’s monthly order quantity for the product (5) (b) Assuming each unit demanded generates a revenue of Rs. 70 and costs Rs. 50. How much will the firm gain or lose in a month if it places an order based on part a. (5) 9. Annual expenditure for medicines was 838 in the north of a country. A sample of 60 individuals showed a per person annual expenditure of 745 in the west of the country. If standard deviation of population was 300. Formulate the hypothesis for a test to determine whether the sample data support the conclusion that the population annual expenditure for medicine is lower in west than in North. (a) What is the p value? (b) At a = 0.01, what is your conclusion? (5+5) 10. What are random sampling methods? (10) 11. A simple random sample with n = 54 provided a sample mean of 22.5 and a sample deviation of 4.4 (a) Develop a 95% confidence interval for the population mean. (b) Develop a 99% confidence interval for the population mean. What happens to the margin of error and the confidence interval as the confidence level increases? (5+5) 3rgp (Excellent) 807