PCQ01 (BUS105) PDF

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In a hypothesis test, the null hypothesis is population mean = 55 and the alternative hypothesis is population mean ≠ 55. A random sample of 26 items is selected. The sample mean is 55.6 and the sample standard deviation is 3.3. Assuming that the population is approximately normal, what should be the degree of freedom associated with this test? Group of answer choices 27 24 25 21 In an Analysis of Variance (ANOVA) procedure. Which of the following is/are assumptions of an ANOVA test? I. The populations follow the normal distribution. II. The populations have equal standard deviations (σ). III. The populations are independent. ______ is the probability of rejecting the null hypothesis when the null hypothesis is true (the claim or alternate hypothesis is not true). Group of answer choices Significance level t-value z-value p-value

When executing an appropriate hypothesis testing, the_________ separates the rejection and non-rejection regions. Group of answer choices critical values. dividing points. limit values. maximum and minimum values. A ________ is a single value (statistic) used to estimate a population value (parameter) whereas a ________ is a range of values within which the population parameter is expected to be found. Group of answer choices variance; confidence interval range; confidence interval point estimate; confidence interval standard deviation; confidence interval If the alternative hypothesis in a hypothesis test includes phrases like “changed”, “not the same” or “different”, the test should be Two-tailed. One-tailed. Is neither one-tailed nor two tailed.

None of the listed choices.

As the degrees of freedom decreases, the shape of the t distribution will stay the same. become flatter. become narrower. it depends on the degree of freedom. In stating a confidence interval, what would happen to a confidence interval if you construct a 90% confidence interval rather than a 99% confidence interval with other parameters being equal? It will be broader. It will not change. The sample size will increase. It will become narrower. When the sample size increases, the I. population mode decreases. II. population standard deviation decreases. III. sampling distribution standard deviation (standard error) decreases. Group of answer choices I, II and III II only III only I only In a two-tailed hypothesis test with a (alpha) = .10, an analyst wants to determine whether a treatment produces an increase or decrease that is significant. What z-score value(s) would define the critical region for this test? Assume population is normal and standard deviation is known. Group of answer choices z < -1.65 and z > 1.65 z < -1.96 and z > 1.96 -1.65 < z < 1.65 -1.96 < z < 1.96 When conducting a hypothesis test, which of the following levels of significance (alpha) will give the lowest Type I error risk? Group of answer choices 0.01 0.05 1.00 0.10 A _________ is a statement about a population parameter subject to verification usually with data from a sample. Group of answer choices

hypothesis estimation claim statistic The mathematics department is conducting an experiment to evaluate if a new teaching method is expected to increase the test scores for students. The population of the test score is known to have a mean of 80. The results will be examined using a one-tailed hypothesis test. Which of the following is the appropriate statement of the alternate hypothesis? Group of answer choices Population mean = 80. Population mean is < 80. Population mean is > 80. There is a five-step procedure that systematizes hypothesis testing. Which of the following step is not in this procedure? I. Construct a confidence interval. II. Select the level of significance. III. Select the test statistic. Group of answer choices None of the listed choices II only III only I only

In performing a hypothesis test, the null hypothesis is population mean = 6.9 and the alternative hypothesis is population mean ≠ 6.9, a random sample of 16 items is selected. The sample mean is 7.1 and the sample standard deviation is 2.0. The population is approximated to be normal. What is the value of computed t for this test? Group of answer choices 0.05 0.33 0.40 0.20 After conducting two-tailed hypothesis test of the population mean with a large sample size, the observed z value was found to be 1.68, with alpha at 0.05. What would be the correct decision? Group of answer choices do not reject the null hypothesis. take a larger sample. not enough information to make a decision. reject the null hypothesis.

_________ has occurred when a true H0 is rejected. Group of answer choices Bias Oversampling Type II error Type I error The volume of detergent in a standard dispenser bottle is normal with a known standard deviation of 0.10 litres. 25 bottles were randomly selected from the production line and found the sample mean to be 1.50. Construct the 95% confidence interval for the mean of the population. Group of answer choices (1.49, 1.51) (-2.00, 2.00) (1.40, 1.60) (1.46, 1.54) Which of the following is/are factors in choosing an appropriate sample size? I. The desired level of confidence, expressed in terms of z. II. The maximum allowable error, E, that the researcher will tolerate. III. The variability in the population under study, measured by σ. Group of answer choices I, II and III II only I only III only

_______ is the probability calculated for the value of the test statistic which is at least as extreme as the one found in the sample data when the null hypothesis is true. F-value z-value t-value p-value A revision course is expected to improve learning in an economics course. Similar tests were given before and after the online revision courses. The scores were captured as S1 and S2 respectively. The difference in scores is computed as d = S2 –S1. Identify an appropriate null hypothesis to execute a hypothesis test. Group of answer choices H : μ ≤ 0. H : S ≠ S. H : μ =0. 0

d

0

1

0

d

2

H : S = S. 0

1

2

When the sample size is increased, what will happen to the 95% confidence interval? Group of answer choices It becomes wider. It becomes a 99% interval. No change. It becomes narrower. In a five-step procedure that systematizes hypothesis testing, which of the following is the initial step? I. State the null hypothesis (H0) and the alternate hypothesis (H1). II. Select the level of significance. III. Select the test statistic. Group of answer choices II only I only None of the listed choices III only Use _________ when the samples are chosen at random from a population that does not exhibit any stratified grouping or naturally occurring grouping. Group of answer choices Dependent sampling Stratified sampling Clustered sampling Simple random sampling In a two-tailed hypothesis test with a (alpha) = .10, an analyst wants to determine whether a treatment produces an increase or decrease that is significant. What z-score value(s) would define the critical region for this test? Assume population is normal and standard deviation is known. Group of answer choices -1.65 < z < 1.65 -1.96 < z < 1.96 z < -1.65 and z > 1.65 z < -1.96 and z > 1.96...