Explore BrainMass
Share

# Descriptive Statistics

### 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

### Standard Deviations, Mean, Confidence Intervals, Margin of Error, and Linear Correlation

1. In a study designed to the 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 from 0 (no pain) to 100 (extreme pain). After given the magnet treatments, the 40 patients had pain scores with a mean

### 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

### The solution gived detailed steps on solving some questions on the topic of descriptive statistics. All formula and calculations are shown and explained.

What differentiates a z test statistic for a population from the z statistic for a sampling of means? Why the difference? Consider a normal population with μ = 43 and σ = 5.2. Calculate the z-score for an x ̅ of 46.5 from a sample of size 16. Find the critical value z a/2 that corresponds to the given confidence level.

### The solution gives detailed steps on determining the percentage of data using empirical rule.

Suppose the data have a bell shaped distribution with a mean of 30 and a standard deviation of 5. Use the empirical rule to determine the percentage of data within each of the following ranges: 20 to 40, 15 to 45, and 25 to 35.

### 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

### Statistics: One-way analysis of variance (ANOVA)

Use data attached. Compute a one-way analysis of variance (ANOVA) to determine whether there are significant age differences across years in college (freshman, sophomores, juniors, and seniors). Report your results in APA format and write a short interpretation. Move your output into a 1-page Microsoft Word document and w

### Determining the Appropriate Sample Size

For the binomial sample information summarized below, indicate whether the sample size is large enough to use the large sample approximation to construct a confidence interval for p. n = 50,^/p = 0.80 Is the sample large enough? Yes, or no and why?

### Call Center Data & Home Market Data

I need quick help. I bought help for each of these problems on this site but have been unable to get help figuring out why there are no calculations in any of the cells, only numbers. The person who posted it was no help and I needed this today (Sunday 7/21). Additionally, there is no explanation for any of the outcomes, as p

### Political Affiliation Bias

Part I: Determine whether an individual's political affiliation affects his or her overall satisfaction with the economy. For this assignment, use only subjects that declared themselves as Republicans or Democrats and leave out any subjects who declared themselves as Independents or Undecided. Analyze any potential difference

### Assessing Confidence Levels

Can you help with this sample question? Choose and calculate the appropriate analysis to compare the confidence levels of participants given consistent feedback on car color and those given inconsistent feedback on car color (the variable name is type of information). Choose and calculate the appropriate analysis to compar

### Normal T and Binomial Distributions

See the attached file. Assume that women's height are normally distributed with a mean given by =63.4 in, and a standard deviation given by =2.7in. If 1 woman is randomly selected, find the probability that her height is less than 64 in. If 46 women are randomly selected find the probability that they have a mean height les

### Operators and Machines

I would like the response to the sample questions below in excel format, so that I can see the formulas used. 11.37 The quality director for a clothing manufacturer wants to study the effect of operators and machines on the breaking strength (in pounds) of wool serge material. A batch of the material is cut into square-yard

### hypothesis testing on biostatistics

1. The mean lifetime for cardiac stents is 8.9 years. A medical device company has implemented some improvements in the manufacturing process and hypothesizes that the lifetime is now longer. A study of 40 new devices reveals a mean lifetime of 9.7 years with a standard deviation of 3.4 years. Is there a statistical evidence of

### Creating multiple linear regressions

Using the data in the Excel file "Home Market Value," develop a multiple linear regression model for estimating the market value as a function of both the age and size of the house. Find a 95% confidence interval for the mean market value for houses that are 30 years old and have 1,800 square feet and a 95% prediction interval f

### Application of Probability

1. Management at the local Randy Rooster Chicken Hut noted 50 percent of the customers order the crispy coating and the remainder order original coating. a. What kind of probability distribution will you use to solve this problem? b. What is the probability that none of the next four customers will request crispy? c. What is

### Assessing a Paired T-test

There are several advantages of using a paired t-test. Since the same subjects are being tested in each of the varying conditions, those subjects serve as their own control. This is a major advantage as you need not consider potential differences between the subjects in the control group and the subjects who are in the experimen

### Predictor Variables

Hassan the file is attached. Betsy is interested in predicting how many 75-year old's will develop Alzheimer's disease and is using as predictors level of education and general physical health graded on a scale from 1 to 10. But she is interested in using other predictor variables as well. With the four predictor variable

### T-Test for Slope in the Regression Analysis

I would be grateful to any experts in regressions for a step-by-step explanation of some simple regression estimations - please see the two attached files. Attached to this post is an Excel spreadsheet which contains two time series, X and Y. To fully understand how the B0 and B1 estimators are estimated, I would be gratef

### One-Sample T-test to Determine if a Sample Population Differs from General Population

Using the data attached, perform the following: Imagine that you have population data with an average height of 5 feet 10 inches. Conduct a one-sample t-test to determine whether your sample population is significantly different from the general population. Imagine that you have population data with an average satisfaction

### One-Sample T-Test

Compute a one-sample t-test comparing the age of your invented sample to the age of the general population of college students in traditional on-ground universities. Assume the population mean is 21. Any other required data may be fabricated. Please include a paragraph of interpretation of the results.

### The solution gived detailed steps on solving some questions on the topic of descriptive statistics. All formula and calculations are shown and explained.

I need help with both of these problems. I have tried everything and I can't figure it out. Problem Set # 6.54. A new dental bonding agent. When bonding teeth, orthodontists must maintain a dry field. A new bonding adhesive (called Smartbond) has been developed to eliminate the necessity of a dry field. However there is

### Calculating Expected Value and Descriptive Statistics

1. A government has specialist who analyze the frequencies of letters of the alphabet in an attempt to decipher intercepted messages. In standard English text, a particular letter used at a rate of 6.8%. a) Find the mean and standard deviation for the number of times this letter will be found on a typical page of 2000 charact

### The solution gived detailed steps on performing sereral hypothesis testings and making detailed analysis for each test. I have done in excel. All formula and calculations are shown and explained.

Using AIU's survey responses from the AIU data set complete the following requirements. TEST #1: Regression Analysis- Benefits & Intrinsic Perform the following Regression Analysis, using a .05 significance level Run a regression analysis using the BENEFITS column of all data points in the AIU data set as the independen

### Questions on Probabilities and Statistical Distributions

1. Heights of men on a baseball team have a bell-shaped distribution with a mean of 185cm and a standard deviation of 6 cm. Using the empirical rule, what is the approximate percentage of the men between the following values? a. 167cm and 203cm b. 179cm and 191cm 2. Heights of women have a bell-shaped distribution with a me

### The solution gived detailed steps on computing measure of association. All formula and calculations are shown and explained.

Please provide detailed steps to solve. Thanks. An epidemiologist found five cases of "big toe cancer" in the Yukon Territory. Because there were only a few cases, the epidemiologist decided to conduct a matched case-control study to determine whether shoe size larger than 9 is a risk factor for big toe cancer. Cases were ind