Dec 4, 2015 | statistics

Explain how the applications of Integer programming differ from those of linear programming. Give specific instances in which you would use an integer programming model rather than an LP model. Provide real-world examples.

Identify any challenges you have in setting up an integer programming problem in Excel, and solving it with Solver. Explain exactly what the challenges are and why they are challenging. Identify resources that can help you with that.

Jul 20, 2015 | statistics

By **Saturday, July 25, 2015**, post your response to the discussion in the**Discussion Area**** **below. Write your initial response in 4 paragraphs. Through**Wednesday, July 29, 2015**, review and comment on at least two peers’ responses.

A random selection of files from a student counseling center revealed the following reasons why college students seek services:

Mental health issues |
25 |

Learning/school issues |
15 |

Relationship issues |
5 |

Other |
5 |

- What does it mean to say the files were randomly selected?
- How would the researcher randomly select files? In other words, what does the process look like?
- What is the probability that if we pulled another student file from the counseling center the student would fall in each of the following categories a) mental health issues, b) learning/school issues OR relationship issues, c) any category except other?
- Would our probabilities and results be different if we used convenience sampling? Why or why not?

Jul 20, 2015 | statistics

A researcher predicts that watching a film on institutionalization will change students’ attitudes about chronically mentally ill patients. The researcher randomly selects a class of 36 students, shows them the film, and gives them a questionnaire about their attitudes. The mean score on the questionnaire for these 36 students is 70. The score for people in general on this questionnaire is 75, with a standard deviation of 12. Using the five steps of hypothesis testing and the 5% significance level (i.e. alpha = .05), does showing the film change students’ attitudes towards the chronically mentally ill?

What does it mean to set alpha at .05?

What is your null hypothesis? Alternate hypothesis?

Is this a one-tailed or two-tailed hypothesis?

What is the critical z?

Calculate the obtained z. Do you reject or fail to reject the null hypothesis?

State in words what you have found.

Jul 9, 2015 | statistics

Using one of the Data Access Tools from the United States Census Bureau, choose some interesting census data and perform a statistical analysis on it in order to answer a question you want to answer with the data. Do not just copy and paste or summarize the data that you find. Use an appropriate statistical tool and provide your thought process behind the tool you chose as as well as the results of your statistical analysis. Use this week’s lecture to aid your analysis. Cite the data source that you chose in APA format.

Respond to at least two of your classmates’ posts.

Jul 8, 2015 | statistics

I need immediate help with statistics online class. can someone just take few exams for me so that I can get a passing grade in the class please.

Jun 29, 2015 | statistics

# STAT 225

*Section* *6380*

## Summer 2015

*Quiz** #3*

**Please ****answer all 10 questions. The maximum score for each question is posted at the beginning of the question, and the maximum score for the quiz is 80 points. Make sure your answers are as complete as possible and show your work/argument. In particular, when there are calculations involved, you should show how you come up with your answers with necessary tables, if applicable. Answers that come straight from program software packages will not be accepted. The quiz is due by midnight, Sunday, July 5, Eastern Daylight Saving Time.**

*IMPORTANT: *Per the direction of the Dean’s Office, you are requested to include a brief note at the beginning of your submitted quiz, confirming that your work is your own.

By typing my signature below, I pledge that this is my own work done in accordance with the UMUC Policy 150.25 – Academic Dishonesty and Plagiarism (http://www.umuc.edu/policies/academicpolicies/aa15025.cfm) on academic dishonesty and plagiarism. I have not received or given any unauthorized assistance on this assignment/examination.

Electronic Signature

Your submitted quiz will be accepted *only if *you have included this statement

Note: In this quiz, you are tested on conceptual understanding of course materials. Therefore, you may use program software or calculator program to determine the mean and standard deviation of any given data set. Also, you may also use appropriate free web applets and tables suggested in the Statistical Resources Modules. However, you do need to show how you come up with your answers. It is important that you show how you come up with the results of your hypothesis testing, and, explain why you do it certain way, if necessary. No credit will be extended to just answers without supporting adequate calculations and arguments. Of course, you need only to show the crucial and critical steps as it is done in the posted homework and quiz solutions.

*Â *The following information is for Questions 1 through 6.

The recommended daily allowance (RDA) of cobalamine (Vitamin B12) for growing teens is

2.4 Âµg (micrograms). My brother takes it upon himself to make sure that everyone gets the message. It is generally believed that growing teens are getting less than the RDA of 2.4 Âµg of cobalamine daily.

It is an open secret that Au & Associates FauxPharmaceutical (FAP) peddles dietary supplements around the globe. It is claimed by representatives of FAP that by taking their vitamin supplement extracted from Atlantic scrod, brand-named as Pillule-au-Sashimi, teens will have the RDA of cobalamine. MÃ©decins Sans FrontiÃ¨res (MSF) has a strong contingent of volunteers in the People’s Republic of Banana. It is in this remote republic MSF is going to take on FAP for good.

MSF volunteers managed to collect with a 24-hour period blood samples of 10 randomly selected teens in the People’s Republic of Banana for cobalamine. The amounts of cobalamine (in Âµg) determined in these 10 randomly selected teens are given as follow:

1.85Â Â Â 2.35Â Â Â 1.87Â Â Â 1.90Â Â Â 1.37Â Â Â 2.35Â Â Â 2.55Â Â Â 2.28Â Â Â 1.95Â Â Â 2.49

Based on their global experience, MSF assumes that the population standard deviation of cobalamine in teens to be 0.56 Âµg.

Now, you are asked to weigh in on the dispute between MÃ©decins Sans FrontiÃ¨res (MSF) and Au & Associates FauxPharamaceutical (FAP).

#### 1.Â Â Â (3 points) Given the above information, what kind of hypothesis test will you conduct? *z*– test, *t*-test, Î©-test, *Ï‡*2-test, *Y*-test, or *F*-test? Please explain.

- (3 points) What will be the null hypothesis, the alternative hypothesis, and, hence, the “
*tailedness*” of the test (left-tailed, right-tailed, or two-tailed)

- (10 points) What is be the corresponding test statistics?

- (5 points) What is the corresponding
*p*-value of the hypothesis test?

- (15 points) What kind of conclusion can you draw from the hypothesis test you have just performed? Of course, representatives of FAP would like to have the conclusion skewed to their And so would the representatives from
*MSF*. What would you do if you are representing FAP? But, if you are representing *MSF*, how would you present your argument?

- (10 points) But, What if
*MSF *actually does not know the population standard deviation in this case, would you conduct your hypothesis test different? Just in case that you are going to perform the hypothesis different, what would you do instead?

The following information is for Question 7.

The tÃªte-Ã -tÃªte between MSF and FAP broke down, as anyone would have anticipated. They are going to court.

To prepare for the upcoming court case, FAP managed to get hold of the same 10 teens randomly selected by MSF, and performed its own testing on them. Their corresponding findings on the teens, in the same order as listed by MSF, are listed below.

2.45Â Â Â 2.85Â Â Â 2.87Â Â Â 2.32Â Â Â 1.98Â Â Â 2.51Â Â Â 1.75Â Â Â 1.98Â Â Â 2.03Â Â Â 2.89

It is understandable that FAP would have findings with a higher level of cobalamine in the teens. But it is important to authenticate FAP’s findings.

It is imperative to make sure that FAP actually have the same group of teens tested by

MSF. His Honor, Judge Ig Sushi is presiding over this landmark case. Unexpectedly, Professor Au is deemed to be able to act impartially, and appointed by His Honor to be the amicus curiÃ¦ in this pending court case. (As a reward for his faithful service, Professor Au will be offered lifelong supply of bananas from the republic.)

After a few tasty bananas, Professor Au suggested to His Honor that the court should perform a statistical test to see if there is any difference in the means of the MSF group and the FAP group based on a court chosen significance level. Furthermore, Professor Au informed His Honor that it would be unlikely that either MSF or FAP actually knew the population standard deviation at all.

#### 7.Â Â Â (16 points) Perform the statistical test recommended by Professor Au. What significance levels do you think MSF would prefer? On the other hand, what significance levels you think FAP would like to set?

The following information is for Questions 8 through 10

For the sake of argument, let us assume that His Honor, Judge Sushi intends to rule in favor of MSF. However, he is rather apprehensive of errors in any statistical testing, especially with respect to Type I and Type II error. Let us assume he picks a 95% significance level to be the benchmark of this court case.

#### 8.Â Â Â (3 points) What is the probability of a Type I error?

- (10 points) What if the RDA of cobalamine is actually not well established in the medical community? In fact, it may span a range of values in Âµg,0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6. What is the corresponding Type II error and power for each of the given assumed RDA value?

- (5 points) Plot the corresponding power curve? What do we observed in this plot? Please

Jun 22, 2015 | statistics

**Experimental Design Problem Set**

**(20 points) **An evaluation was done to find effective ways to reduce bullying at the middle school level in a small state. This program randomly assigned middle schools to four groups and provided to the schools in the treatment groups the resources and technical support to implement an anti-bullying peer support program. Below is a description of the experiment.

Researchable question: Does peer support, coupled with education, reduce bullying in middle school?

Subjects: Public middle schools.

Independent variable (treatment): Anti-bullying education coupled with a peer support and mentoring program between seventh and eighth grade students..

Dependent variable: Self-reported bullying experiences (among both bully and victim)

Design diagram:

R Â Â Â Â Â Â Â O Â Â Â Â Â Â Â X Â Â Â Â Â Â Â O

R Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â X Â Â Â Â Â Â Â O

R Â Â Â Â Â Â Â OÂ Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â O

R Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â O

**(10 points)** What type of design is being employed in this experiment? Discuss how this would be administered and the justification for the four groups from a standpoint of validity.

**(10 points)** What are the practical disadvantages of including the no-pretest groups in this experiment?

**(50 points) **Concerned about rising rates of obesity and Type 2 diabetes among young adolescents, Whitcomb County implemented a public health program to improve adolescent healthy eating and increase exercise. Physicians in the Countyâ€™s wellness center referred at risk teenagers (based on Body Mass Index) to the program.Â Â Of 600 youth referred, 450 entered the program. Of these, 150 were referred to a nutritionist to develop a healthy eating program; 150 were involved in an after-school exercise program, and 150 were enrolled in both the nutrition and exercise program. The 150 youth who did not choose to enter the program agreed to be monitored as a control group. A variety of health measures were gathered prior to beginning the program and for several intervals during the program.

**(10 points) ** Use the R X O notation to summarize the design.

**(20 points) ** Shortly after the study started, the area high schools banned vending machines and implemented healthier school lunches.

- Would this affect the internal validity of the study? Why or why not?

- Would this affect the external validity of the study? Why or why not?

**(10 points)** A number of the students involved in the exercise program ran into conflicts with after school sports programs. The study administrator permitted them to move to the nutrition-only group. Discuss the effect on internal validity. What should the administrator have done?

**(10 points)** Discuss the selection of the no-treatment group. What issues does it raise for internal validity?

**(25 points)** In the late 1980s the Tennessee state legislature funded a four-year experiment to evaluate the effect of small class sizes on learning. The experiment compared different class arrangements for children in kindergarten through third grade:

– a regular-size class (size 22-25 pupils) with a single teacher â€“ the control group

– a small class (size 13-17 pupils) with a single teacher â€“ the treatment group

Each participating school had at least one class of each type. Within schools both pupils and teachers were randomly assigned to one of the two types of classes. Each year the children were given standardized tests (the SAT).

**(15 points)** In the excel file you will find the reading and math scores of the 2^{nd} grade boys and girls. Please fill out the table below and use the standard significance levels of (*t<.05; **t<.01; ***t<.001) to determine the effects.

**(15 points) **In 1-3 paragraphs (250 words max), please summarize the results. Does being in a small class positively affect student test scores?

Jun 17, 2015 | statistics

Examine the literature inÂ human resources and identify five articles published within the past five years that investigate mediating, moderating, or independent variables in an attempt to contribute to theory in the topic area. Write a paper in which for each article, you:

- Describes the theory the researchers explore. What are the key constructs in the theory? How are they related? Identify which ones are cause, effect, mediating, or moderating constructs. How are the constructs operationalized?
- Briefly describe the study, including the number of participants and research methods.
- Briefly describe the statistical analyses used
- Briefly described the findings and how the researchers interpreted them and their contribution to theory.

Using some or all of the five articles, argue for a gap in the knowledge in the topic area and briefly describe a study involving mediator and or moderator variables that can contribute to theory.

Support your paper with a minimum of 5 resources. In addition to these specified resources, other appropriate scholarly resources, including older articles, may be included.

Length: 5-7 pages not including title and reference pages

References: Minimum of 5 scholarly resources.

Your paper should demonstrate thoughtful consideration of the ideas and concepts that are presented in the course and provide new thoughts and insights relating directly to this topic. Your paper should reflect scholarly writing and current APA standards. Review APA Form and Style.

Jun 17, 2015 | statistics

# statistics

Imagine you are a manager at a major bottling company. Customers have begun to complain that the bottles of the brand of soda produced in your company contain less than the advertised sixteen (16) ounces of product. Your boss wants to solve the problem at hand and has asked you to investigate. You have your employees pull thirty (30) bottles off the line at random from all the shifts at the bottling plant. You ask your employees to measure the amount of soda there is in each bottle. Note: Use the data set provided by your instructor to complete this assignment.

Write a two to three (2-3) page report in which you:

- Calculate the mean, median, and standard deviation for ounces in the bottles.
- Construct a 95% Confidence Interval for the ounces in the bottles.
- Conduct a hypothesis test to verify if the claim that a bottle contains less than sixteen (16) ounces is supported. Clearly state the logic of your test, the calculations, and the conclusion of your test.
- Provide the following discussion based on the conclusion of your test:

- If you conclude that there are less than sixteen (16) ounces in a bottle of soda, speculate on three (3) possible causes. Next, suggest the strategies to avoid the deficit in the future.

**Or**

- If you conclude that the claim of less soda per bottle is not supported or justified, provide a detailed explanation to your boss about the situation. Include your speculation on the reason(s) behind the claim, and recommend one (1) strategy geared toward mitigating this issue in the future.

Your assignment must follow these formatting requirements:

- Be typed, double spaced, using Times New Roman font (size 12), with one-inch margins on all sides. Â No citations and references are required, but if you use them, they must follow APA format. Check with your professor for any additional instructions.
- Include a cover page containing the title of the assignment, the studentâ€™s name, the professorâ€™s name, the course title, and the date. The cover page and the reference page are not included in the required assignment page length.

Jun 12, 2015 | statistics

You have been hired as a consultant for a company that would like to start a new marketing campaign to increase their online sales.

They have given you data for 840 of their customers and would like to know who they should target in their new campaign (e.g., should they develop an app for a specific OS, should they target a certain age group, etc.).

Using your knowledge of statistics, create a report explaining your specific recommendations and rationale behind them.Â Include any tables, charts or graphs you feel are necessary.

I have attached an example how this project should be done. Please add graphs to support your marketing idea.

Thank you

Jun 10, 2015 | statistics

we started by learning how to calculate and interpret z-scores to identify how a single score (X) compares to the population of all scores based on the mean and standard deviation. You also learned about the importance of a normal distribution for using the Unit Normal Table and z-scores to find the probabilities associated with randomly selecting certain scores (X) from a population (without access to the raw data from the population). This discussion is designed to get you to think a little more about the normal distribution and how z-scores are used to identify how single scores compare to the population of all scores.

provide an example of a variable you expect to be normally distributed in the population (if a Likert scale is used to measure this variable provide the survey question and response scale). Why do you think this variable is normally distributed? What do you think the mean (Î¼) and standard deviation (Ïƒ) would be in the population? Where would you fall on the distribution in terms of your z-score (based on your expected Î¼ and Ïƒ)?

Jun 10, 2015 | statistics

Independent t test

We will start with the data file (â€œActivity 4a.savâ€). Suppose, however, you [the researcher] encountered a small problem during data collection: after the post-tests were collected, you realized that the post-test form did not ask for the studentsâ€™ identification number. As such, it will be impossible to match pre-test scores to post-test scores. Rather than simply give up, you start thinking about the data you do have and try to determine whether you can salvage your project. In assessing the situation, you realize that you have 40 pre-test scores and 40 post-test scores, but no way to link them. While it will result in a weaker comparison, you determine that you are still able to compare pre-test vs. post-test scores; you will use a between-subjects design rather than a within-subjects design.

- Create the data set.
- Using the â€œActivity 4a.savâ€ file as a starting point, create a new dataset that you can use with the between subjects design. Hint: you will no longer need the variables CreativityPre and CreativityPost. Instead, you have only one variable for the score on the creativity test. A second (or grouping) variable will serve to indicate which test the student took.
- Save this dataset as Activity 4b.sav and remember to submit the file.

- Exploratory Data Analysis/Hypotheses.
- Perform exploratory data analysis on theÂ creativity variable in the new dataset,

Activity 4b.sav. Using SPSS, calculate the mean and standard deviation using the

grouping variable.
- Construct appropriate charts/graphs that display the relevant information using

the grouping variable.
- Write the null and alternative hypotheses used to test the question above (e.g., whether participation in the course affects writing scores).

- Comparison of Means
- Perform an independent t test to assess your hypotheses above.
- In APA style, write one or two paragraphs that describe the dataset, gives your hypothesis, and presents the results of the dependent sample t test.

- Comparison of Designs
- You used the same dataset to analyze both a between- and within-subjects design. Create a single paragraph (using the material you wrote above), that presents both sets of results.
- Explain, in 300-500 words, whether the two tests resulted in the same findings. Did you expect this to be the case? Why or why not? What have you learned in this assignment?

Jun 10, 2015 | statistics

Dependent Sample T-test

In this activity, we are interested in finding out whether participation in a creative writing course results in increased scores of a creativity assessment. For this part of the activity, you will be using the data file “Activity 4a.sav”. In this file, “Participant” is the numeric student identifier, “CreativityPre” contains creativity pre-test scores, and “CreativityPost” contains creativity post-test scores. A total of 40 students completed the pre-test, took the creativity course, and then took the post-test.

1. Exploratory Data Analysis/Hypotheses

a. Perform exploratory data analysis on CreativityPre and CreativityPost. Using SPSS, calculate the mean and standard deviation of these two variables.

b. Construct an appropriate chart/graph that displays the relevant information for these two variables.

c. Write the null and alternative hypotheses used to test the question above (e.g., whether participation in the course affects writing scores).

2. Comparison of Means

a. Perform a dependent t test to assess your hypotheses above (note that many versions of SPSS use the term “paired samples t test” rather than “dependent t test”; the test itself is the same.

b. In APA style, write one or two paragraphs that describe the dataset, gives your hypothesis, and presents the results of the dependent sample t test.

Jun 10, 2015 | statistics

ANOVA

All of us have had our blood pressure measured while at our physicianâ€™s office. How accurate are these measurements? It may surprise you to learn that there is something called â€œwhite coat syndromeâ€â€”the tendency of some people to exhibit elevated blood pressure in clinical (medical) settings only. In other words, for these people, the very fact that the physician is taking their blood pressure causes it to increase In this activity, you will be using the â€œActivity 4c.savâ€ data file to determine whether you find support for the existence of white coat syndrome. In this study, 60 participants were randomly assigned to one of three groups. The â€œsettingsâ€ variable indicates the location in which the participantsâ€™ blood pressure was recorded: 1=home, 2=in a doctorâ€™s office, and 3=in a classroom setting. The â€œSystolicBPâ€ variable contains the participantsâ€™ systolic pressure (the â€œupperâ€ number). The â€œDiastolicBPâ€ variable contains the participantâ€™s diastolic pressure (the â€œlowerâ€ number).

Exploratory Data Analysis/Hypotheses.

- Perform exploratory data analysis on both the SystolicBP and DiastolicBP variables. Using SPSS, calculate the mean and standard deviation of these two variables. Be sure that your analysis is broken down by setting (e.g., you will have six means, six SDâ€™s, etc.).
- Create two graphsâ€”one for systolic and one for diastolic pressure. Each graph should clearly delineate the three groups.
- Write a null and alternative hypothesis for the comparison of the three groups (note that your hypothesis will state that the three groups are equivalent; be sure to word your null hypothesis correctly).

- ANOVA.
- Using the â€œActivity 4c.savâ€ data file, perform two single factor ANOVAs: one using SystolicBP and one using DiastolicBP as the dependent variable.
- If appropriate for either or both of the ANOVAs, perform post hoc analyses to determine which groups actually differ.
- Write one paragraph for each ANOVA (be sure to use APA style). At a minimum, each paragraph should contain the three means, three SDâ€™s, ANOVA results (F, df), post hoc tests (if applicable), effect size, and an interpretation of these results.

Your submittal should demonstrate thoughtful consideration of the ideas and concepts that are presented in the course and provide new thoughts and insights relating directly to this topic. Where applicable your submittal should reflect scholarly writing and current APA standards. Review APA Form and Style.

May 22, 2015 | statistics

Create your own 3-question entertainment survey or using thisÂ General Opinion SurveyÂ or another free survey program or thisÂ link. Secure a minimum of 20 responses. Your survey respondents may be friends, family or classmates. (**Note:**Â The small sample size was chosen for convenience, and as you know, is not a valid sample. The goal is for you to create, deploy, and analyze a simple survey.)

Create Excel charts of your results and describe those charts in words. (You will receive no credit for charts that are copied from the survey software.)

- Include a copy of your survey
- Provide charts of your results and describe those charts in words
- Explain how the results of your survey can be used by a media group or company

This section of the paper will contain 1 page of text and 3 charts.

May 22, 2015 | statistics

Review the Ballard Integrated Managed Services, Inc. (BIMS), Part 1 case study overview (attached)

Prepare a 300-400 word written report along with a 2- 3 slide MicrosoftÂ® PowerPointÂ® presentation for the senior management team to present your findings.

Address the following:

- Identify the level of measurement for each of the (4 levels) variables involved in the study.

May 22, 2015 | statistics

Please read all of homework post… Follow the assignment to the tee (assignment in red writing).. Â List resources and must be completed by 10:30 PM on 05/20/15Â Â Â Thank You 🙂

**Review the coding form example in Figure 7.1 on page 136 of your course text (See Attached)..**

**Choose a setting where you would enjoy observing behavior. It might be someplace you go everyday (like the grocery store) or it might be a place you would like to go (such as a city park).**
**Create a coding form for your hypothetical observational study. Use the coding sheet in the course text as an example, but make up something that is entirelyÂ ***your own*.
**Upload your coding form as an attachment (in doc or rtf format) to your posting.**

**With these thoughts in mind:**

**Post** by **Day 3:**

**The topic of your hypothetical observational study. This should also be the â€œSubjectâ€ field of your post this week (e.g., â€œChild Playground Behaviorâ€). **
**In the main body of your post, provide background information on your hypothetical observational study including the setting, why you are interested in this study, and what you hope to learn.**
**Explain whether you would be an acknowledged or unacknowledged observer andÂ ***why*.
**Describe the types of behavior and the episodes you included on your coding form.**
**Upload the coding form you created as an attached document. **

**Note: Be sure to support your postings and responses with specific references to the Learning Resources**

Attachments:

May 22, 2015 | statistics

A researcher wishes to study the effect of a new drug on blood pressure.Â Answer and explain all questions

- Would you recommend using a
*z*-test, a *t*-test, or an ANOVA for the analysis?Â Explain your answer.
- What would your choice of test depend on?Â For the test you select, explain your design and your comparison groups.
- Would the hypothesis be directional or non-directional?
- Would the test be one-tailed or two-tailed?
- What would be the null and what would be the alternative hypothesis?