Please select the correct answer and explain briefly why:

1. In order to test the effectiveness of a drug called XZR designed to reduce cholesterol levels, 20 heart patients' cholesterol levels are measured before they are given the drug. The same 20 patients use XZR for two continuous months. After two months of continuous use the 20 patients' cholesterol levels are measured again. The comparison of cholesterol levels before vs. after administering the drug is an example of testing the difference between:

A. Two means from independent populations
B. Matched pairs from two dependent populations
C. Two means from independent populations with unknown variances
D. Two means from independent populations with equal variances

2. If the t statistic (critical value) is used in lieu of the Z statistic when comparing two means from independent populations using small samples, the probability of rejecting the null hypothesis __________.

A. Increases
B. Decreases
C. Remains the same
D. Depends on whether the population is normal

Solution Summary

The solution provides answers to multiple choice questions on hypothesis testing. Short explanation of the answer is also included.

With regard to hypothesis testing about two means, what is the distinction between two independentpopulations and two related populations? Be specific but brief in about 4 or 5 paragraphs, if possible.

1.Why would you use a small sample to draw inference about a large population?
Test of a single proportion:
2. What is the difference between a sample parameter (X-bar and s) and a proportion parameter (p)?
Test of two populations, large sample size (z-statistics)
3. When would you use two population test with a larg

Need help with one psychological research question that could be answered by each of the following types of statistical tests:
a) Z test and T test for independent samples
b) T test for dependent samples
c) Rationale for both selections so I might be able to understand better

Please choose the correct answers and write briefly why:
For a given multiple regression model with three independent variables, the value of the adjusted multiple coefficient of determination is _________ less than R2.
a. Always
b. Sometimes
c. Never
d. Can be greater or less depending on the standard error

1. Give a scenario that would require you to use a non-parametric statistic, such as ranking.
2. Also choose any statistician and find an interesting fact about them.
Please provide an answer of good quality, length and merit.

You are interested in a new method of advertising. In order to test the new procedure they have tested it in eleven markets with the following sales in thousands of dollars: $124; $157; $98; $190; $103; $135; $149; $176; $200; $180; and $256. You also used eleven control markets, which had the following sales in thousands of d

1. In testing whether the means of two normal populations are equal, summary statistics computed for two independent samples are as follows: Assume that the population variances are equal. Then, the Pooled Variance is equal to:
A) 0.1017
B) 1.2713
C) 0.3189
D) 1.1250
2. Two samples

General Questions on Probability and Analysis of Variance.
STATISTICS QUESTIONS:
1. Which of the following is a correct statement about a probability?
a. Probability values range from 0 to 1, inclusive.
b. Probabilities may assume negative values.
c. Probabilities may be greater than 1.
d. Probabilities are limited to