Tag: Statistics

American Airlines Flight 171 from New Yorks’ JFP airport to LAX airport in Los Angeles uses an Airbus A321 aircraft with 189 seats available for passengers. American Airlines can overbook by accepting more reservations than there are seats available. If the flight is not overbooked, the airline loses revenue from empty seats, but if too many seats are sold, the airline loses money from the compensation it must pay to the bumped passengers. Assume that there is a 0.0995 probability that a passenger with a reservation will not show up for the flight (based on data from the IBM research paper “Passenger-Based Predictive Modeling of Airline No-Show Rates” by Lawrence, Hong, and Cherrier). Also assume that American Airlines accepts 205 reservations for the 189 seats that are available and that passengers are independent of each other.
Using StatCrunch’s calculators, find the probability that when 205 reservations are accepted for American Airlines Flight 171, there are more passengers showing up than there are seats available. Is the probability of overbooking small enough that it does not happen very often, or does it seem too high so that changes must be made to make it lower?
Use trial and error to find the maximum number of reservations that could be accepted so that the probability of having more passengers than seats is 0.05 or less.
What do you think about this policy of overbooking flights? Is it a good thing, a bad thing, or a little of both? Why do you think that?

This will be a written assignment for my doctoral quantitative analysis class regarding linear regression.

Using the attached data (“Car Weight and MPG.sav”), compute and interpret the relationship between:
* Car Weight (“Weight”) and miles per gallon consumed (“CityMPG”)
* Sample = cars in the dataset. Population = all cars on the road in Illinois in 2020.

Instructions:

For this regression analysis, state the following:
* A clear research question appropriate for a linear regression: (e.g., Among population A, is X a significant predictor of Y?”)
* Null and research hypotheses that align clearly and neatly with your RQ.
* Descriiption of the variables used.
* Your dependent and independent variables. (Clearly explain your rationale as to why which is which.)
* State the sample size, along with the mean, standard deviation, and range (min

This will be a written assignment for my doctoral quantitative analysis class regarding T-Tests.

Using the attached data (i.e., “job satisfaction” and “survey”), perform one analysis (Part A) using a dependent (or paired) samples t-test and the other (Part B) using the independent samples t-test. Determine appropriate test for each relationship, and then proceed with your analyses. (To be clear, you are required to perform TWO t-tests in this assignment.)

Part A
Teachers at ACE Charter School were given a 20% raise in their salary in August of 2015. Of all the teachers at ACE, 30 of them were asked to participate in a study to assess the effect of the pay raise on their overall job satisfaction. How was their job satisfaction (“0” = very unsatisfied to “50” = very satisfied) affected as a result? (Note: You can make causal inferences in this analysis.) (Sample = 30 ACE teachers in the study. Population = all ACE teachers.)
* What is the research question? (Use “difference” or “effect” language as we are no longer talking about “relationship” among variables but differences between groups or an effect of X on a particular population.)
* What is the null hypothesis?
* What is the research hypothesis? (Directional)
* Basic descriiptive analysis appropriate for the variables used (e.g., mean, median, range, SD, etc.) in a paragraph form. (Don’t just include a number of SPSS tables and not talk about it.)
* State the rationale for applying either independent or dependent t-test in this investigation using appropriate readings and resources in Module 6. (Please cite specific references.)
* Write out the results in an APA format. (Use the appropriate example below as your template.)
* Please include appropriate tables from the SPSS output used in your analyses.

Part B
Using a sample of 575 participants from River Forest, IL, compare the average years of education (variable name = “educ”) between men and women in this city. (Note: Avoid causal inferences here, and just talk about the differences between men and women in the analysis.) (Population = all adults in River Forest, IL.)
* What is the research question? (Use “difference” language as we are no longer talking about “relationship” among variables but differences between groups.)
* What is the null hypothesis?
* What is the research hypothesis? (Non-Directional)
* Basic descriiptive analysis appropriate for the variables used (e.g., mean, median, range, SD, etc.) in a paragraph form along with the SPSS output showing the descriiptive results. Be sure to analyze the years of education by men and women separately. An aggregate analysis of years of education would not be of much use here.
* State the rationale for applying either independent or dependent t-test for in this investigation using appropriate readings and resources in Module 6. (Please cite specific references.)
* Write out the results in an APA format. (Use the appropriate example below as your template.)
* Please include appropriate tables from the SPSS output used in your analyses.
An Example of a Paired-Samples t-Test Result Write Up
“Using a sample of 100 participants, a paired-sample t-test was conducted to compare the number of words recalled (from 0 to 15) in ginkgo and placebo conditions. There was a significant difference in the number of words recalled for ginkgo (M = 6.23, SD = 3.91) and placebo (M = 4.35, SD = 3.45) conditions; t(99) = 4.12, p < .001. These results suggest that consumption of ginkgo is related to a significant or meaningful increase in one’s memory, by about two points. The size of the effect (using Cohen's d) is medium at .51.”
An Example of an Independent Samples t-Test Result Write Up
“Using a sample of 200 participants, an independent samples t-test was conducted to compare the number of words recalled (from 0 to 15) in ginkgo (n = 100) and placebo (n = 100) groups. There was a significant difference in the number of words recalled for ginkgo (M = 7.95, SD = 3.91) and placebo (M = 5.85, SD = 3.60) groups; t(198) = 1.99, p = .03. These results suggest that ginkgo group had greater word recall than their placebo counterparts, by about two words. The size of the effect (using Cohen’s d) is medium at .56.”

I have attached the SPSS output and relevant material for each part, as well as recommended resources to elaborate on the assignment expectations. Make sure to provide substantial evidence from scholarly resources and refrain from making generalized statements. Textbooks, blogs, magazine or internet articles, book chapters, or special reports, do not count toward scholarly resources.

The powerpoint slides provided come from the class textbook, which should be the primary source used to support your statements (Salkind, N.J.

1. A patient is classified as having gestational diabetes if their glucose level is above 140 milligrams per deciliter (mg/dl) one hour after a sugary drink is ingested. Rebecca’s doctor is concerned that she may suffer from gestational diabetes. There is variation both in the actual glucose level and in the blood test that measures the level. Rebecca’s measured glucose level one hour after ingesting the sugary drink varies according to the Normal distribution with μ= 140 X mg/dl and σ = X 1 mg/dl, where X is the last digit of your GCU student ID number. What is the probability of Rebecca being diagnosed with gestational diabetes if her glucose level is measured:

a. Once?
b. X 1 times, where X is the last digit of your student ID?
c. X 4 times, where X is the last digit of your student ID?

Comment on the relationship between the probabilities observed in (a), (b), and (c). Explain, using concepts from lecture, why this occurs and what it means in context.

2. Suppose next that we have even less knowledge of our patient, and we are only given the accuracy of the blood test and prevalence of the disease in our population. We are told that the blood test is 9X percent reliable, gestational diabetes affects X 1 percent of the population in our patient’s age group, and that our test has a false positive rate of X 4 percent. Compute the following quantities based on this new information:

a. If 100,000 people take the blood test, how many people that test positive will actually have gestational diabetes?
b. What is the probability of having the disease given that you test positive?
c. If 100,000 people take the blood test, how many people that test negative despite actually having gestational diabetes?
d. What is the probability of having the disease given that you tested negative?

Comment on what you observe in the above computations. How does the prevalence of the disease affect whether the test can be trusted?

3. As we have seen in class, hypothesis testing and confidence intervals are the most common inferential tools used in statistics. Imagine that you have been tasked with designing an experiment to determine reliably if a patient should be diagnosed with diabetes based on their blood test results. Create a short outline of your experiment, including all of the following:

a. A detailed discussion of your experimental design.
b. How is randomization used in your sampling or assignment strategy?
c. The type of inferential test utilized in your experiment.
d. A formal statement of the null and alternative hypothesis for your test.
e. A confidence interval for estimating the parameter in your test.
f. An interpretation of your p-value and confidence interval, including what they mean in context of your experimental design.

This assignment uses a rubric. Please review the rubric prior to beginning the assignment to become familiar with the expectations for successful completion.

APA style is not required, but solid academic writing is expected.

IQ Tests and the Normal Distribution – IQ tests are a type of assessment that measures cognitive abilities. They provide a score that is intended to serve as a measure of an individual’s intellectual abilities and potential. IQ scores follow a normal distribution, i.e. bell curve.
Begin by reviewing the normal distribution and how to calculate probabilities associated with it:
• This video will review the important features of the normal distribution, https://www.youtube.com/watch?v=mtbJbDwqWLE
• This video shows how to calculate probabilities using the normal distribution in Statcrunch, https://www.youtube.com/watch?v=H_O2GcFCDCw
Next, review the websites below that discuss various IQ tests and how their scores are distributed:
• This website reviews the types of IQ tests (Weschler IQ Test and Stanford-Binet) and how they compare on the normal curve, http://www.assessmentpsychology.com/bellcurve.htm
• This website provides IQ classifications (Very Superior, Superior, High Average, Average, Low Average, Borderline, Extremely Low), and the IQ scores that are associated with those classifications for the Wechsler Adult Intelligence Test, http://www.assessmentpsychology.com/iqclassifications.htm
In your main post, do the following:
1. Select a particular IQ test, such as the Weschler or Stanford-Binet.
a. Describe how the IQ test measures intelligence.
b. Proide the mean and standard deviation of the test.
c. Discuss what score values fall within 1, 2 and 3 standard deviations of the mean and what the Empirical Rule tells us about this.
2. Select a random IQ score.
a. Calculate the probability of a person scoring at least this high. In other words, the probability of a person achieving this score or a higher score. You may use technology to find this value.
b. How is this score classified on the IQ test’s scale (i.e. Average, Above Average, etc.)?
c. Based on the information above, do you think this score is appropriately classified? Please explain from a statistical standpoint as well as a personal perspective.

• The first assignment of the project consists of a descriiptive analysis that motivates the research question and the proposed hypothesis, the statement of the research question and of
the guiding hypothesis in such a way that they can be analyzed through statistical inference
methods. The students are asked to identify a research question that is relevant for them,
state the hypothesis and motivate the relevance of the research question and the proposed
hypothesis.
• The second assignment of the project asks students to state the causal mechanisms that they
want to analyze in the study using the different tools of the potential outcomes framework
and, in general, those of causal analysis.
• Finally, the students are asked to identify the appropriate empirical strategy for their question, providing a robust argument for their methodological selection and highlighting the
data necessary to address the research question with the specified empirical strategy to obtain causal results. The students are not asked to perform the empirical analysis themselves,
but if they are motivated to do so, the effort will be rewarded.
1
Advanced Quantitative Methods
Grades
The project as a whole represents 20% of the course’s final grade. Each partial submission represents 5% of the final course grade, and the final, complete submission represents the 10% left.
As the partial submissions will receive feedback from the instructor, the 10% of the final submission will not necessarily correspond to the performance in the partial submissions. However,
submission of the materials in the intermediate due dates is mandatory for the final submission
to be considered towards the final grade of the cours

BUSAD265 Article Review #2 Assignment
For this assignment, select an article from the following list. Read the article and write a 1- 2 page review that includes the following 3 sections:
Summary: (1/2 page) Briefly summarize the article. Be careful, comprehensive, and concise in your summary.
Critique: (1 page) Discuss the pro/cons of the article’s main points. Do you agree or disagree with the author—- and more importantly, why do you agree or disagree? This section of your report is the most difficult to write. The important material for this section is how you justify your position. Specifically address whether or not the author is using statistics in an appropriate manner, or if they are using them to make a point that the stats cannot justify!
Tie-in: (1/2 page) Where and how do the points discussed in the article tie-in or relate to the ideas and concepts discussed in class? You may additionally tie-in the article to your career plans. Carefully consider the tie-in connection when you are selecting your article.
Write the article review using the template in Blackboard – it’s there to help you!
50 points.
Use the following to review:
Gallup: Worries About Personal Data Top Facebook’s Users’ Concerns
http://news.gallup.com/poll/232343/worries-personal-data-top-facebook-users-concerns.aspx

For this assignment, select an article from the following list. Read the article and write a 1- 2 page review that includes the following 3 sections:
Summary: (1/2 page) Briefly summarize the article. Be careful, comprehensive, and concise in your summary.
Critique: (1 page) Discuss the pro/cons of the article’s main points. Do you agree or disagree with the author—- and more importantly, why do you agree or disagree? This section of your report is the most difficult to write. The important material for this section is how you justify your position. Specifically address whether or not the author is using statistics in an appropriate manner, or if they are using them to make a point that the stats cannot justify!
Tie-in: (1/2 page) Where and how do the points discussed in the article tie-in or relate to the ideas and concepts discussed in class? You may additionally tie-in the article to your career plans. Carefully consider the tie-in connection when you are selecting your article.
Write the article review using the template in Blackboard – it’s there to help you!
100 points.
Choose ONE of the following to review:
New York Times: Wage Inequality is Falling
https://www.nytimes.com/2018/03/01/opinion/wages-low-paid-workers.html
Bloomberg: US CEO’s Earn 140 Times More Than the Typical Worker
https://www.bloomberg.com/news/articles/2018-02-01/ceos-in-u-s-seen-earning-140-times-more-than-the-typical-worker
The Wall Street Journal: Single-Payer Heathcare Isn’t Worth the Wait
https://www.wsj.com/articles/single-payer-health-care-isnt-worth-waiting-for-1516566456
Washington Post: How Striking West Virginia Teacher’s Salaries Compare
https://www.washingtonpost.com/news/politics/wp/2018/03/02/how-striking-west-virginia-teachers-salaries-compare-to-teachers-in-other-states/?utm_term=.20495c44871d
New York Times: America’s Real Digital Divide
https://www.nytimes.com/2018/02/11/opinion/america-digital-divide.html
Forbes: Crypto-currencies Slammed as Speculative Mania
https://www.forbes.com/sites/rogeraitken/2018/03/02/cryptocurrencies-slammed-as-speculative-mania-by-central-banker-carney-cites-high-bitcoin-fees/#73d318af4404

This is a quantitative study, see the attachment. Please respond to all comments on the right side of the paper. It is unknown to what extent nurses’ age and years of practice predict their spiritual care. Please answer all of the questions in the attachment. This is a ordinal logistic regression analysis and please add detail information about this analysis along with what assumptions are needed to be met and as to meet these assumptions. Feel free to change anything else that you see needs to be corrected. Please see the sections on data analysis procedures and Research Questions and Hypotheses were they clearly state a detail write on ordinal logistic regression analysis is needed along with its assumptions. Please identify predictor and criterion variables; the nature of the variables. Please respond to ALL comments and highlight what you add to the attachment.

Create an example of a research design that would call for a repeated measures ANOVA. Be sure to describe the research question, the independent variable(s), the levels of the independent variable(s), and the dependent variables. In your discussion, mention ways that the research question could have been answered using a between-subjects design.