Refer to the MegaStat/Excel Output for the Wilcoxon Signed Ranks

question 55

Multiple Choice

Refer to the MegaStat/Excel output for the Wilcoxon signed ranks test given in the table below.
At a significance level of .01,which one of the following rejection point conditions is correct regarding the null hypothesis H₀: D₁ and D₂ are identical probability distributions and the alternative hypothesis of H_a: D₁ is shifted to the left of D₂.

• A)We reject H₀ and conclude there is not sufficient evidence that the probability distribution of population 1 is shifted to the left of the probability distribution of population 2.
• B)We cannot reject H₀ and conclude there is not sufficient evidence that the probability distribution of population 1 is shifted to the left of the probability distribution of population 2.
• C)We reject H₀ and conclude there is very strong evidence that the probability distribution of population 1 is shifted to the left of the probability distribution of population 2.
• D)We failed to reject H₀ and conclude there is very strong evidence that the probability distribution of population 1 is shifted to the left or to the right of the probability distribution of population 2.
• E)We failed to reject H₀ and conclude there is very strong evidence that the probability distribution of population 1 is identical to the probability distribution of population 2.

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Definitions:

Sampling Error

The difference between a population parameter and a sample statistic that results from selecting a sample.

Expected Value

The predicted average outcome of a random variable, computed as the weighted average of all possible values.

Stratified Random Sampling

A probability sampling method in which the population is first divided into strata and a simple random sample is then taken from each stratum.

Strata

Subsets of a population that are known to be homogeneous with respect to some characteristic, used in stratified sampling.