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Descriptive Statistics

Generating 95% Confidence Intervals

Data was collected in a clinical trial evaluating a new compound designed to improve wound healing in trauma patients. The new compound was compared against a placebo. After treatment for 5 days with the new compound or placebo, the extent of wound healing was measured and the data are shown in the table below. Suppose that clin

Statistical Analysis for a Random Sample

Independent random samples from approximately normal populations produced the results shown below. Complete parts a and b. Sample 1: 42, 29, 38, 37, 40, 40, 22, 39, 57, 55 Sample 2: 70, 55, 50, 54, 52, 23, 30, 30, 43, 61 a. Do the data present sufficient evidence to conclude that u1 - u2 does not equal 0? Use alpha = 0.

Probability, Normal Distribution, Binomial Probabilities

1. A brand name has 80% recognition rate. If the owner of the brand wants to verify that rate beginning with a small sample of 15 randomly selected consumers, find the probability that exactly 12 of the 15 consumers recognize the brand name. Also find the probability that the number who recognize the brand name is not 12. The p

Solving Multiple Questions on Descriptive Statistics

1. Determine whether the description corresponds to an observational study or an experiment. Forty patients with skin cancer are divided into two groups. One group an experimental drug to fight cancer, the other a placebo. After two years, the spread of the cancer is measured. Does the description correspond to an observatio

Various Statistical Situations

Compute the mean, median, and mode for the following three sets of scores. Do it by hand or using Excel. Show your work. Score 1 Score 2 Score 3 3 34 154 7 54 167 5 17 132 4

Chi-Square Analysis: Sex vs. Year of College

Can you help with this sample question...Please end the solution in a doc file so I can open it..also could you send the minitab solution as well it helps me to follow...Thanks Conduct a chi-square analysis to determine whether sex and the year in college are related. Report your results in APA format and write one to two sen

Logistic Multiple Regression Analysis Using SPSS

Thank you for your hard work on this - here is a note from a friend who is working on the same issue - he is referring to the SPSS input: The correct analysis was to run a hierarchical logistic regression entering perceive, safety and gender in the first block and previous, selfcon and sexexp in a second. I used forced entry

Statistics: Probability with a Roulette Wheel and Population Data

Question: A roulette wheel has 38 slots, numbered 0, 00, and 1 to 36. The slots 0 and 00 are colored green, 18 of the others are red, and 18 are black. The dealer spins the wheel and at the same time rolls a small ball along the wheel in the opposite direction. The wheel is carefully balanced so that the ball is equally likely

Graduating with Debt

University %w/debt amount$ College %w/debt amount% Pace 72 32,980 Wartbug 83 28,758 Iowa State 69 32,130 Morehouse 94 27,000 Mass. 55 11,227 Wellesley

Methods and Random Variables

Consider the experiment of tossing a coin twice. 1. List the experimental outcomes. 2. Define a random variable threat that represents the number of heads occurring on the two tosses. 3. Show what value the random variable would assume for each of the experimental outcomes. 4. Is the random variable discreet or continuous?

Stats: Normal Distributions, Sample Means, and Null Hypotheses

1. To test Ho: μ=20 versus H1: μ<20, random sample size n=12 is obtained from a population that is known to be normally distributed with σ=2. a. If the sample mean is determined to be 18.3, compute P-value. b. If the researcher decides to test this hypothesis at the a=0.05 level of significance, will the researcher rejec

Higher Levels of Stress and Lower Levels of Confidence

Can you help with this sample question and send the solution in a doc file so I can open it.... For this assignment, use the data This week, you will explore the hypothesis that higher levels of stress are associated with lower levels of confidence. Compute the correlation between the stress score and confidence scores

Correlation: Age and Height Scenario

Can you help me with this sample question, the required data is in the attached Excel document. For this assignment, determine whether there is a correlation between age and height. Move your output into a Microsoft Word document and write a 1- to 2-sentence, APA-formatted interpretation of the results.

Working with Correlated Variables

Determine whether the variable hours worked per week by an individual are correlated to the variable of the individual's satisfaction with his or her job. Be sure to use the proper df and show all the steps of the calculations. Also include an explanation of how the critical value was determined. Be sure to interpret the results

Correlation: Happiness and Wealth

You are interested in knowing whether wealthier people are happier. You collected data from fifty people about their incomes and their overall happiness levels on a scale of 1 to 10. Upon analyzing the results, you find that the correlation coefficient has a value of −0.25. On the basis of this data, respond to the following:

The solution gives detailed steps on solving 5 statistical problems using normally distributed data such as finding confidence intervals, finding z-score and finding p-value. All formula and calculations are shown and explained.

1. In a study designed to test the effectiveness of magnets for treating back pain, 40 patients were given a treatment with magnets and also a sham treatment without magnets. Pain was measured using a scale 0(no pain) to 100 (extreme pain). After given the magnet treatments, the 40 patients had pain scores with a mean of 10.0 an

Compute the standard error of the sample mean.

Question: Suppose N = 80000, n = 16000 and s = 50. a. Compute the standard error of the sample mean using the finite population correction factor. b. Repeat part a assuming n= 32000. c. Repeat part a assuming n = 80000. d. Compare parts a, b and c, and describe what happens to the standard error of the sample mean as n i

Determining the Sampling Distribution

Question: If you wish to estimate a population mean with a sampling distribution error SE = 0.28 using a 95% confidence interval and you know from prior sampling that sigma^2 is approximately equal to 5.4, how many observations would have to be included in your sample?

Solve: 99% Confidence Interval

7. The random sample shown below was selected from a normal distribution. 8, 3, 6, 10, 6, 3 Complete parts a and b. Construct a 99% confidence interval for the population mean. Round to two decimal places as needed. Assume that the sample mean and sample standard deviation remains exactly the same as those you just calc

Chi-Square Tests and Nonparamatric Tests

12.7) Some people enjoy the anticipation of an upcoming product or event and prefer to pay in advance and delay the actual consumption/delivery date. In other cases, people do not want a delay. An article in the Journal of Marketing Research reported on an experiment in which 50 individuals were told that they had just purchased

Critical Values and Confidence Levels

1. Do one of the following as appropriate. a) Find the critical value z_(a/2), b) find the critical value t_(a/2), c) State that neither the normal nor the t distribution applies. Confidence level 95%; n=20; ơ is unknown; population appears to be normally distributed. 2. Given: The paired sample data of the age and alcohol co

ANOVA Analysis Table

Use the table below to answer the series of questions. Elaborate on your answers as to how you arrived at the solution. a) What is the sample size? b) Use the information and determine a Tukey simultaneous 95% confidence interval for italic mu subscript 1 - italic mu subscript 2. The mean and sample sizes for brand 1 an

Political Affiliations, Critical Values, and Post Hoc Analysis

Using the data attached, help with the following. Determine whether an individual's satisfaction with the economy differs across the various political affiliations, using the levels of Republican, Democrat, and others (e.g., Independents and Undeclared). Use the proper df and show all the steps of calculations. Explain

Post Hoc Tests

Consider the different post hoc tests discussed in the readings and respond to the following: Describe the general rationale behind using post hoc tests (i.e., when they are used and why). One of the advantages of using an ANOVA (compared to using t-tests) is also a disadvantage—using an ANOVA makes it necessary to use

Using ANOVA in Statistical Analysis

See the attached file for data. This week, you will explore the hypothesis that recall will vary as a function of stress levels. Conduct an ANOVA comparing participants' recall at Time 1 across all three stress-level conditions (low, medium, and high). Conduct post hoc tests if needed, using the Tukey method. Move y