Question

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Assignment Description

After the completion of IDL 3 Preliminary and final assignments, you will have completed a probabilistic analysis and presented the findings in a memorandum in the role of a Forensic Engineer. This document will be sent to the Court involved with a class action lawsuit that involves the product you will be evaluating. For this purpose, you will address your memorandum to the Judge. However, it must be understandable to the jury who will reference it, and it is also likely to be referenced by the lawyers on both sides of the litigation.

Assignment Reading and Preparation

You will be expected to discuss the elements of this assignment accurately. There are several areas in which students had difficulty in the past that you may want to make sure you are familiar with by doing some additional research

    • Carefully read the problem description; use the Polya method to be sure you consider all the information provided and evaluate how you will analyze the problem. If you feel you need more input on the objects being discussed reference the articles that the assignment images are from or other credible sources.
    • Be sure you are clear on the difference between the data you have been provided and your evaluation of it.
    • Be sure you understand the difference between negligence and liability. These terms are often used incorrectly (see workshop 6 slides).
    • Review class-action lawsuit(Links to an external site.) (Links to an external site.)Links to an external site. to be sure you understand what you are dealing with (see workshop 6 slides).

The follow are recommendation and resources that can help you with the assignment, many were used to support workshop 6

    • Find general audience discussions of both hypothesis testingand P-test – seeing these descriptions can help you figure out how to talk about your problem.  One excellent source is Medium, an online open publication, among those publishing here are many tech professionals (however, you need to look at their credentials). This site is a subscription service but if you An example of a good option is: do a search with “hypothesis test” and Medium OR ‘p-test’ and medium you should get a number of options you can view for free. One example of a good article is – Everything you Should Know about p-value from Scratch for Data Science by Sharoon Saxena, Senior Machine Learning Engineer at Oracle

For anyone who is interested in additional reading:

Problem

In 2022, a wildfire burned more than 10,000 acres in Isley, a small city on the edge of Florida’s Everglades. The fire damaged 89 homes, businesses, and other structures and caused over $42 million in damages. Wildfires require certain environmental conditions to spread, but the initial sparks sometimes come from electrical utility equipment and power lines. An investigation found that the origin of the Isley fire was a transmission tower, where one of the rows of hanging insulators had fallen to the ground. The insulators are designed to protect the tower from the electrical current flowing through the power lines, and they are hung with metal rings, called C-hooks. These C-hooks were manufactured by Seabyrd Iron Works, Inc, who claims that the hooks should not wear more than 5 mm over a fifty-year lifespan. In cooperation with the power company, an independent investigator was hired by the city of Isley to collect data on a random sample of the C-hooks at various transmission towers in the area. It was found that several of the hooks were eroding at a faster rate than was promised by the Seabyrd Iron Works when the local electric company purchased and installed them throughout their electric power system in the 1981.

 

The local utility company has blamed Seabyrd Iron Works, Inc. for manufacturing sub-standard parts that have worn prematurely. Civil litigation against the manufacturer has ensued, and a class-action lawsuit has been brought forth. In a class-action lawsuit, a certified group of individuals – a group called Isley Homeowners, in this case – sues the defendant for financial damages, claiming that the C-hooks provided in 1981 were not manufactured up to standard. The judge in this case has requested an impartial expert witness, and you have been brought in as a forensic engineer. Forensic engineers investigate the causes of failure in engineering projects ranging from faulty machinery to collapsed buildings. You will analyze the data the independent investigator collected and come to a statistically informed conclusion with a confidence level of 99% on whether the C-hooks used on transmission towers in Isley have already exceeded their promised wear of not more than 5.0 millimeters in 50 years. 

 

The data provided by the independent investigator is below. Because it would be infeasible to test every C-hook in the area, eight transmission towers (labeled in the first column) were randomly selected, and the level of wear on the six C-hooks on each tower was measured. Does this sample data suggest that the average C-hook supplied by Seabyrd Iron Works has passed 5.0 mm in wear?

You will provide your findings in a memorandum addressed to the judge, Tanya Wasilew, and copied to the defense attorney, Mitch Soldano, and the plaintiffs’ attorney Amira Herana. Remember that you are writing to convince the jury.

Data File xlsx  Download Data File xlsx  

Technical Input

While the problem statement above is fictional. However, C-hook failures on a transmission tower were the purported causeLinks to an external site. of the 2018 Camp Fire in California. The utility company settled with a bankruptcy court and agreed to pay $1 billion in damages from several fires in the area. Below are photographs of the C-hook installations to give you information on the object you will be writing about. 

 

Figure 1: C-hooks are responsible for holding up insulators on towers, which protect the metal tower from electrical current flowing through the power lines.

Source: Gafni, M. & Peele, T. (2018, December 7). If was originally built in 1919. What failed on PG&E tower at heart of Camp Fire probe? The Mercury News. https://www.mercurynews.com/2018/12/07/it-was-originally-built-in-1919-what-failed-on-pge-tower-at-heart-of-camp-fire-probe/Links to an external site.

 

Figure 2: The Broken C-Hook determined to have caused the 2018 Camp Fire

Source: Tube Time (2020, September 16)

https://twitter.com/tubetimeus/status/1306362075044667392Links to an external site.

 

Figure 3: A worn C-Hook

Source: Van Derbeken, J (2019, December 7) New images of PG&E hooks on  Camp Fire power line released. NBC Bay Area. https://www.nbcbayarea.com/investigations/new-images-of-pge-hooks-on-camp-fire-power-line-released/2190709/Links to an external site. 

 

Compose Content

Review and evaluate the problem presented – Using the tools learned in IDL 3 evaluate the problem: what you know, the significance of what you know to the problem, and what information you have that can be used in a statistical problem.  Determine the appropriate hypothesis test to use, given what input you have, the problem, and the statistical tools you have learned. Additionally, determine the appropriate use of the null and alternative hypotheses for the problem.  If it helps you can sketch a diagram of the problem.

Complete the calculation – Complete the statistical analysis of the problem.  Be clear that you understand all of the processes you have completed to get your answer, you will have to document it.

Develop your document for the assigned audience and purpose – As you will have templates to use with many professional documents you will create, this assignment has a format that you must follow – the Legal Memorandum Template.  Download the Legal Memorandum Template.This format includes appearance and content. See the Exemplar Download Exemplarfor a visual guide.

Memorandum Header – This section of the document provides the information a reader needs to know to determine if they need to read the rest of the document.  It must be consistent in layout and format so that it is easy to read. This section is graded on your ability to follow directions.

TO – The person you have been asked to address the memorandum to. Follow the exemplar, on paper a judge’s title is ‘Honorable’.

Why? This section and the CC section may be addressed to one or more person(s). The amount of information included for each is dependent on an organization’s level of formality and the role of hierarchy in the organization. National culture may also play a role in these decisions, as some may place greater importance on titles (such as Mr., Dr., or General). The person’s role title is often included, as it will dictate what type of information they need from you. Finally, the location of the addressee can be included, when it also suggests the type of information the document will include. When in doubt, it is better to be more formal and include too much information than to find out it was needed but not included.

CC – Emulate the format of the example. The name of each person being addressed is on a new equally indented line.

FROM – Emulate the format of the example. Use your name, your title is Forensic Engineer

DATE – Use the due date of the assignment format as Month, day, year (i.e June 22, 2022).

RE – For a lawsuit, this will have the suit name and then what it is about relative to the lawsuit.

Question Presented – Present specifically, and concisely the question you are being asked to address. This question must include a technical and legal component.

Brief Answer – Present specifically, and concisely the answer you got from your analysis. This answer must include a technical and legal component. The answer will not have details on your analysis or numeric outcomes.

Facts – This section will present the input you were given by presenting the context, the data and its meaning in the context, and how this input allows you to structure an analysis to determine an answer. It will not proceed into the analysis.

Discussion – This section presents the logic on how you analyzed the problem in language a non-technical audience can understand, starting with the most basic reasoning for the use of this analysis for the problem. This section will end with what you found through your analysis and what it means for the case.

Conclusion – This summarizes the entire document ending with the outcome of your analysis and its meaning to the case.

Appendix – This section is on its own page (use ‘insert/page break). For this section type out the mathematics, you used to calculate an answer in detail, ending with the outcome, what it means for the hypothesis test and the case.

Assignment Deliverable, Due Date, Questions, and Submittal

Deliverable: Use the the Legal Memorandum Template Download the Legal Memorandum Template for your assignment, following the example Download exampleprovided. Download e provided.

This assignment will be completed as a (modified version) of a legal memorandum as documented by CUNY School of Law. (You should not reference their document, as a full legal memorandum is much more complex than what you will be doing.)

Download example

Document Length: Well done documents are generally 3 – 4 pages; 1.5 – 2.5 pages for the main part of the memorandum and 3/4 – 1 page for the appendix. Documents shorter than this are likely not well done.

No quotations and no plagiarism –  Quotations are rarely used in professional engineering and computer science writing; do not get in the habit of doing this. Ethically completed work must have at its core your own thinking built upon credible knowledge of experts that proceeded you.  Also unacceptable is:

  • Using the words of others without quotation marks and in-text citations
  • Using the words of others, but reorganizing the sentence structure (This is a form of plagiarism called inappropriate paraphrasing.)
  • Using the words of others, but changing a few words in each sentence (This is a form of plagiarism called inappropriate paraphrasing.)

The words in your document must represent your own thinking, based on the information you have gathered.  Citing credible sources from which you got ideas gives you credibility and it is required in this work.