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Descriptive Statistics

Waiting Lines and Queuing Theory Models Q14-23 Bill First, general manager of Worthmore Department Store, has estimated that every hour of customer time spent waiting in line for the sales clerk to become available costs the store \$100 in lost sales and goodwill. Customers arrive at the checkout counter at the rate 30 per hou

Biostatistics: Assessing Significance

A study is conducted to estimate the effect of a low-carbohydrate diet on cholesterol level. In this study, participants' cholesterol levels are measured before starting the program and then again after 6 months on the program. The data are shown below. Before Program 210 230 190 215 260 200 After 6 Months 215 240 19

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

The solution gived detailed steps on performing a hypothesis testing for significance of correlation. All formula and calcuations are shown and explained.

6. a. Compute the correlation between age in months and number of words known. b. Test for the significance of the correlation at the .05 level of significance. c. Interpret this correlation. (see attached file for data)

The solution gived detailed steps on performing a hypothesis test on astima case. All formula and calcuations are shown and explained.

Please provide steps to solve. A randomized controlled trial is run to evaluate the effectiveness of a new drug for asthma in children. A total of 250 children are randomized to either the new drug or placebo (125 per group). The mean age of children is assigned to the new drug is 12.4 with standard deviation of 3.6 years. Th

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

The solution gived detailed steps on performing a hypothesis testing on two population proportions. All formula and calcuations are shown and explained.

A certain researcher thinks that the proportion of women say that the earth is getting warmer is greater than the proportion of men. In a random sample of 250 women, 70% said that the earth is getting warmer. In a random sample of 220 men, 68.18% said that the earth is getting warmer. At the .05 significance level, is ther

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

The solution gived detailed steps on performing chi square test. All formula and calcuations are shown and explained.

Chi square compares actual data with expected data. What would the expected data be? For example, if I know the percentage of brown M&Ms in a bag is 40% set by the company, but I open up a bag that is 50% brown M&Ms, I could run a chi square to see if there is a significant difference. This might lead the company to see that

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

The solution gived detailed steps on solving various questions on the normally distributed data. All formula and calcuations are shown and explained.

Albany Automotive is a specialized auto and body shop and mostly serves residents in the Eastern part of Albany. The chief mechanic has determined that the time to paint automobiles is uniformly distributed and that the required time ranges between 45 minutes to 1 1/2 hours. a. Write the function for the probability density f

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 testing correlation coefficient and then interpretating it. All formula and calcuations are shown and explained.

Given the following information, use Table B.4, which is; values of the correlation coefficient needed for rejection of the null hypothesis. I'm certain you have access to said table. Use the table to determine whether the correlations are significant and how you would interpret the results. The correlation between speed and

The solution gived detailed steps on solving various questions on the descrptive statistics. All formula and calcuations are shown and explained.

1. Find range, variance, and standard deviation. Identify one reason why the standard deviation from this sample might not be a good estimate of the standard deviation for the population of adults. 56 54 64 67 58 2. Below are 36 sorted ages of an acting award winner. Find p60 method: 16 23 24 26 30 32 32

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

Correct Statement Analysis based on Learning Curve Equation

which statement is correct? Y = 1250(X)-0.120294 Y is the cost of the first unit. The slope equals 1 - 0.120294 = .8797 or 87.97% Y represents the cost of the 1250th unit The slope equals 92%

PSY2008W5A1 Researchers were interested in learning the effects of trans fats on levels of cholesterol in the blood. Two different research designs were constructed.

Researchers were interested in learning the effects of trans fats on levels of cholesterol in the blood. Two different research designs were constructed. Part I: Between-Groups Design In the between-groups design, researchers were interested in whether cholesterol levels would differ depending on diet. Twenty participants we