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Descriptive Statistics

Calculating the Binomial Probability

1. Heights of women have a bell shaped distribution with a mean of 161cm and a standard deviation of 6cm. Using Chebyshev's theorem, what do we know about the percentage of women with heights that are within 2 standard deviations of the mean? What are the minimum and maximum heights that are within 2 standard deviations of the m

Descriptive Statistic Calculations

1. Heights of men on a baseball team have a bell shaped distrubtion with a mean of 172cm and a standard deviation of 7cm. Using that is the empirical rule, what is the approximate percentage of the men between the following values? a) 165 cm and 179cm b) 151cm and 193cm 2. Heights of women have a bell shaped distribution with

Two-Sample Tests

I would like the response to the questions below in excel format, so that I can see the formulas used. 10.11 Digital cameras have taken over the majority of the point-and-shoot camera market. One of the important features of a camera is the battery life, as measured by the number of shots taken unit the battery needs to be r

Directional and Non-Directional Hypotheses

Can you help with this sample question? When computing a t-test, it is important to distinguish between directional and nondirectional hypotheses as the direction will determine the rejection regions. Describe how the rejection regions would differ according to the type of hypothesis you would use. An insurance company ask

Correlation Matrix and Regression Analysis

Conduct a correlation matrix using the Forbes 500 dataset. Determine which variables have a significant relationship. Select an independent and dependent variables and run a regression analysis. What can you conclude from the findings?

Binomial Probabilities and Binomial Random Variables

1. Suppose we want to determine the (binomial) probability (p) of getting 8 heads in 10 flips of a 2-sided coin. Using the binomial probability table in the appendix of the text, what values of n, v, and p would we use to look up this probability and what would be the probability? 2. If x is a binomial random variable, use th

Identifying Null and Alternative Hypotheses for Various Problems

(1) In the past, the average age of employees of a large corporation has been 40 years. Recently, the company has been hiring older individuals. In order to determine whether there has been an increase in the average age of all the employees, a sample of 64 employees was selected. The average age in the sample was 45 years with

A Hypothesis Tesing With Asthma Case

Please provide steps to solve. The mean PEF for children free of asthma is 306. An investigator wants to test whether children with asthma have restricted PEF. A sample of 40 children are studied and their mean PEF is 279 with a standard deviation of 71. Is there statistical evidence of a lower mean in PEF in children with as

A chi-square test for independence of three groups

Please provide steps to solve the following question. A study is designed to investigate whether there is a difference in response to various treatments I patients with chronic pain. The data are shown below. Are symptoms independent of treatment? Conduct a chi square test at a 5% level of significance. Df = ? Critical val

Chi-Square Test for Independence of Two Groups

Please provide steps for the question below: A study is designed to investigate whether there is a difference in response to various treatments for patients with chronic pain. The data is shown below. Is there a statistically significant difference in the proportions of patients who show improvement? Between treatment 1 and

Constructing a confidence interval for population mean

Please provide steps to solve the question below. The following are BMI scores for 12 patients. Generate a 95% confidence interval estimate of the true BMI. 25 27 31 33 26 28 38 41 24 32 35 40 Upper limit of CI: Lower limit of CI:

A hypothesis testing for population mean using

Please provide steps to solve this question. The mean BMI in patients free of diabetes is 28.2. The investigator hypothesizes that BMI is much higher. Based on the data, is there evidence that BMI is significantly higher than 28.2? Use a 5% level of significance. 25 27 31 33 26 28 38 41 24 32 35 40 Critical Value = t =

Statistics: Hypothesis Tests and Chi Square Tests

The TMC Daily News reported that the color distribution for plain N&N'S was: 40%brown, 20%yellow 20% orange, 10% green, and 10% tan. Each piece of candy in a random sample of 100 plain N&N'S was classified according to color, and the results are listed low. Use a 0.05 significance level to test the claim that the published color

Comprehension of Statistics

1. Given a sample size of 65, with sample mean 726.2 and sample standard deviation 85.3, we perform the following hypothesis test. H0: μ= 750 H1: μ< 750 What is the conclusion of the test at the level? Explain your answer 0.10α= 2. Consider the hypothesis test given by : H0: μ = 530 H1: μ=≠ 530 In a random samp

Sample and Population Descriptive Statistics

1. The Gallup Organization contacts 1,426 undergraduates who attend a college and live outside the U.S. and asks whether or not they had taken a course in a conversational English during their studies. -What is the population in the study? -What is the sample in the study? 2. Identify the type of observational study (cros

Conducting a Literature Review for Empirical Articles

Can you help with this sample exercise I have no clue what a empirical study is... In Part I, you will perform a literature review and select two empirical articles on a research topic of your choice. Both articles must be on the same general topic. Provide a summary of both articles that includes the following information,

Correctly Identifying Type I and Type II Errors

Confidence in recall differs depending on the level of stress. Recall for participants in high-stress conditions will deteriorate over time. Boys will have higher levels of confidence than girls. For each hypothesis listed above, indicate: A type I error and a type II error, given the context of the hypothesis Whethe

The solution gived detailed steps on classifying dependent and independent variables and then deciding the relevant Statistical Techniques. Each question is explained in details.

Write the following: - Dependent Variable (DV) and Independent Variable (IV) - Level of Measurement of each Variable (Nominal, Ordinal, Interval, Ratio) - Look up the Statistical Technique on the attached matrix - Briefly explain your reasoning for assigning the variables, DV and IV A: Is there a relationship between the

Concepts of Statistics and Parameters

1. Determine whether the given value is a statistic or a parameter and explain. In a study of all 4171 students at a college it is found that 25% own a television. 2. Determine whether the value is from a discrete or continuous data set. Number of notes in a song 24. 3. Determine whether the given description corresponds

Describe a Situation in Which you would test a Directional Hypothesis

Thank you for the help with the last question your response helped me better understand.. Directional and nondirectional hypotheses can be easily interchanged according to the hypothesis the researcher is testing. For instance, a drug company might predict that a drug will help a subject lose weight while another drug company