Qnt 275 Statistics for Decision Making Final Exam
QNT 275 Statistics For Decision Making Final Exam 1) The main purpose of descriptive statistics is to
A. summarize data in a useful and informative manner
B. make inferences about a population
C. determine if the data adequately represents the population
D. gather or collect data 2) The general process of gathering, organizing, summarizing, analyzing, and interpreting data is called
B. descriptive statistics
C. inferential statistics
D. levels of measurement 3) The performance of personal and business investments is measured as a percentage, return on investment. What …show more content…
A. negatively skewed
B. positively skewed
D. bell shaped 19) The mean of any uniform probability distribution is
A. (b – a)/2
B. (a + b)/2
C. Σ x/ η
D. nπ 20) For the normal distribution, the mean plus and minus 1.96 standard deviations will include about what percent of the observations?
D. 68% 21) For a standard normal distribution, what is the probability that z is greater than 1.75?
D. 0.9599 22) A null hypothesis makes a claim about a
A. population parameter
B. sample statistic
C. sample mean
D. Type II error 23) What is the level of significance?
A. Probability of a Type II error
B. Probability of a Type I error
C. z-value of 1.96
D. Beta error 24) Suppose we test the difference between two proportions at the 0.05 level of significance. If the computed z is -1.07, what is our decision?
A. Reject the null hypothesis.
B. Do not reject the null hypothesis.
C. Take a larger sample.
D. Reserve judgment. 25- Which of the following conditions must be met to conduct a test for the difference in two sample means? 1. Data must be at least of interval scale.
2. Populations must be normal.
3. Variances in the two populations must be equal.
4. Data must be at least of interval scale and populations must be normal. 26- For a hypothesis