1 A shoe store developed the following estimated regression equation relating sales to inventory investment (x1) and advertising expenditures (x2) . Sales= 25 + 10*x1 + 8x2 Estimate sales resulting from a $15 investment in inventory and an advertising budget of 10$. Select one \" a. b. c. d. e. Predicated sales are $100 You cannot calculate the predicated value since it is only a speculation predicated sales are $ 255 Predicated Sales are $25 Predicated sales are $245 Q2 In an article about the cost of health care, Money magazine reported that a visit to a hospital emergency room for something as simple as a sore throat has a mean cost of $400 (Money, January 2009). Assume that the cost for this type of hospital emergency room visit is normally distributed with a standard deviation of $100. What is the probability that the cost will be more than $500? a. b. c. d. e. 3.34% 15.87% 22.78% 61.45% 91.22% Q3 A shoe store developed the following estimated regression equation relating sales to inventory investment (x1) and advertising expenditures (x2) . The interpretation of the sample estimate for inventory investment is : a. As the inventory investment increases by the $1 so sales increase by $10 keeping advertising expenditure constant . b. As the inventory investment increases by the $1 so sales increase by $10 c. None of the above answers correct d. As the inventory investment increases by the $1 so sales increase by $43 e. As the inventory investment increases by the $1 so sales increase by $8 Q4 In an article about the cost of health care, Money magazine reported that a visit to a hospital emergency room for something as simple as a sore throat has a mean cost of $400 (Money, January 2009). Assume that the cost for this type of hospital emergency room visit is normally distributed with a standard deviation of $100. What is the probability that the cost will be lower than $350? a. b. c. d. e. 30.85% 7.02% 12.45% 63.12% 90.01% Q5- if extreme values occur in the data set, which of the following measures of central tendency are the most appropriate: a. b. c. d. e. The variance The median The standard Deviation The mode The mean Q6 The U.S. Department of Education reports that about 50% of all college students use a student loan to help cover college expenses (National Center for Educational Studies, January 2006). A sample of 10 students who graduated with student loan debt (in $1000) is shown here. 10.1 14.8 5.0 10.2 12.4 12.2 2.0 11.5 17.8 4.0 Please choose the correct answer ; a. The third quartile is equal to 12.4 and means that 75% of the students have a debt lower $12,400 and 25% have a debt higher than $12,400 b. The third quartile is equal to 5.0 and means that 75% of the students have a debt higher than $ 5,000 and 25% debt lower than $5,000. c. The third quartile is equal to 12.4 and means that 75% of the students have a debt higher than $12,400 and 25% debt lower than $12,400 d. The third quartile is equal to 5.0 and means that 75% of the students have a debt lower than $5,000 and 25% debt higher than $ 5,000 e. None of these answers . f. Q7. The following statistics were collected on two groups of shipments Group A Group B sample size 45 30 sample mean 100 lbs 800 lbs sample std. dev 80 lbs 70 lbs Which of the following statements is correct? a. Group A is less variable than Group B because Group A's standard deviation is larger b. Group A is relatively less variable than Group B because Group As coefficient of variation is smaller c. Group A is less variable than Group B because the std deviation per animal is smaller d. Group A is relatively more variable than Group B because the sample mean is larger e. Group A is more variable than Group B because the sample size is larger Q8- If two variables, x and y, have a very strong linear relationship, then A. there is evidence that x causes a change in y B. there is evidence that y causes a change in x C. there might not be any causal relationship between x and y D. there must be a causal relationship between x and y E. None of these alternatives is correct Q9 From the above picture choose the best answer : 1. Which variable/s would you drop in the final model with level of significance of 10% : a. b. c. d. e. All MPotential and MShare Account and MShare Time and Account Intercept 2. The regression Line is : a. Y= -1507+ 2,01*time + 0,0372*MPoten + 199,08*MShare + 5,55*Accounts b. Y= 778,6*Sales + 1,93*time + 0,0082*MPoten + 67,03*MShare + 4,77*Accounts c. Y= 778,6 + ,93*Time + 0,0082*Mpoten + 67,03*MShare + 4,77*Accounts d. Y= -1,94 + 1,04*Time + 4,54*Mpoten + 2,97*MShare + 1,16*Accounts e. Y= -1507*Sales + 2,01*Time + 0,0372*Mpoten + 199,08*MShare + 5,55*Accounts 3. a. b. c. Which statement is true ( level of significance 5%): None of them is true MPotenial is Not statistically significant MPotenial is Not statistically significant because the estimated coefficient is very low. d. MPotenial is Not statistically significant since the standard error is large. e. MPotenial is statistically significant since the P-Value is less than 5%. Which of the following is not a true statement about the binomial probablity distribution? A) Each outcome is independent of each other B). The random variable of interest is continous C) The probability of success must be constant from trial to trial If extreme values occur in the data set, which of the following measures of central tendency are the most appropriate A. The mean B. The median C. The mode D. The variance E. The standard deviation 7. Suppose the daily sales of a small corner shop are as follows: Daily sales: Monday: $100, Tuesday: $60, Wednesday: $75, Thursday: $90, Friday: $50. Please choose the correct answer: A. mean =75, median = 75, mode = 75 B. mean =75, median = 75, mode = 50 C. mean =75, median = 75, mode = does not exist D. mean =75, median = 75, mode = 100 E. None of the previous answers The probability distribution for a discrete random variable which is used to compute the probability of x successes in n trials is known as the A. normal probability distribution B. standard normal distribution C. binomial probability distribution D. none of the above 8. Suppose the daily sales of a small corner shop are as follows: Daily sales: Monday: $100, Tuesday: $60, Wednesday: $75, Thursday: $90, Friday: $50. The range of the data is? A. 100 B. 200 C. 50 D. 375 E. None of the previous answers Q7- If two events are mutually exclusive, then their intersection probability A. will always be zero B. can have any value larger than zero C. must be larger than zero, but less than one D. none of the choices are correct 46. A standard normal distribution is a normal distribution A. with a mean of 1 and a standard deviation of 0 B. with any mean and any standard deviation C. with a mean of 0 and any standard deviation D. with a mean of 0 and a standard deviation of 1 E. none of the above If two variables, x and y, have a very strong linear relationship, then A. there is evidence that x causes a change in y B. there is evidence that y causes a change in x C. there might not be any causal relationship between x and y D. there must be a causal relationship between x and y E. None of these alternatives is correct A shoe store developed the following estimated regression equation relating sales to inventory investment (X1) and advertising expenditures (X2): Sales = 25 + 10*X1 + 8*X2 The interpretation of the sample estimate for inventory investment is: A. As the inventory investment increases by $1 so sales increase by $8 B. As the inventory investment increases by the $1 so sales increase by $10 C. As the inventory investment increases by the $1 so sales increase by $10 keeping the advertising expenditure constant D. As the inventory investment increases by the $1 so sales increase by $8 keeping the advertising expenditure constant E. None of the above If the outcome of event A is not affected by event B, then events A and B are said to be A. mutually exclusive. B. statistically independent. C. collectively exhaustive. D. None of the above