QNT 561 Final Exam
Exam 3
1. A difference between calculating sample mean and population mean is
A. Only in symbols, we use instead of µ and n
... [Show More] instead of N
B. We divide sum of observations by n - 1 instead of n
C. observations are ranked and select middle value for population mean
D. There are no differences
2. Which of following measures of central location is affected most by extreme values?
A. Median
B. Mean
C. Mode
D. Geometric mean
3. Which level of measurement is required for median?
A. Nominal
B. Ordinal
C. Interval
D. Ratio
4. In which of following distributions is probability of a success usually small?
A. Binomial
B. Poisson
C. Hyper geometric
D. All distribution
5. Which of following is not a requirement of a probability distribution?
A. Equally likely probability of a success
B. Sum of possible outcomes is 1.00
C. outcomes are mutually exclusive
D. probability of each outcome is between 0 and 1
6. Which of following is not a requirement of a binomial distribution?
A. A constant probability of success
B. Only two possible outcomes
C. A fixed number of trails
D. Equally likely outcomes
7. A sample
A. Is a part of population
B. Has more than 30 observations
C. Is usually identified as N
D. All of above
8. difference between sample mean and population mean is called
A. Population mean.
B. Population standard deviation
C. Standard error of mean
D. Sampling error
9. Suppose a population consisted of 20 items. How many different sample of n = 3 are possible?
A. 6840
B. 1140
C. 20
D. 120
10. A point estimate is
A. Always an estimate of population mean
B. Always equal to population value
C. An estimate of population parameter
D. None of above
11. We wish to develop a confidence interval for population mean. population follows normal distribution, standard deviation of population is 3, and we have a sample of 10 observations. We decide to use 90 percent level of confidence. appropriate value of to represent level of confidence is
A. z =1.65
B. z = 1.96
C. t = 1.833
D. t = 1.812
12. A confidence interval
A. Always includes population parameter
B. Decreases in width as sample size is increased
C. Cannot include a value of 0
D. None of above
13. Special Rule of Addition is used to combine
A. Independent events
B. Mutually exclusive events
C. Events that total more than one
D. Events based on subjective probabilities
14. We use General Rule of Multiplication to combine
A. Events that are not independent
B. Mutually exclusive events
C. Events that total more than 1.00
D. Events based on subjective probabilities
15. An experiment is a
A. Collection of events
B. Collection of outcomes
C. Always greater than 1
D. act of taking a measurement or observation of some activity
16. Which of following statements is true regarding a sample?
A. It is a part of population
B. It must contain at least five observations
C. It refers to descriptive statistics
D. All of above are correct
17. Which of following statements is true regarding a population?
A. It must be a large number of values
B. It must refer to people
C. It is a collection individuals, objects, or measurements
D. None of above
18. A nominal scale variable is
A. Usually result of counting something
B. Has a meaningful zero point
C. May assume negative values
D. Cannot have more than two categories
19. In a two-sample test of means for independent samples, equal sign always appears in
A. null hypothesis
B. alternate hypothesis
C. upper tail of test statistic
D. None of above
20. alternate hypothesis
A. Is accepted if null hypothesis is rejected
. Will always contain equal sign
. Tells value of sample mean
. None of above [Show Less]