The Ethics of the Hyatt Regency Hotel Collapse

Assigning the responsibilities of the designer, the builder, and the owner of a project is an important issue in civil engineering. It is one of the biggest factors in assigning blame for structural failures (which was particularly evident in the infamous Kansas City Hyatt Regency Walkways Collapse). It is not always clear who should be held responsible for an incident. This can be exacerbated by inconsistent stories between parties. Establishing a consistent system for organizing responsibilities between parties could diminish this issue and even make our modern structures safer.

On July 17, 1981, the Hyatt Regency Hotel in Kansas City, Missouri, held a videotaped tea-dance party in their atrium lobby. With many party-goers standing and dancing on the suspended walkways, connections supporting the ceiling rods that held up the second and fourth-floor walkways across the atrium failed, and both walkways collapsed onto the crowded first-floor atrium below. The fourth-floor walkway collapsed onto the second-floor walkway, while the offset third-floor walkway remained intact. As the United States’ most devastating structural failure, in terms of loss of life and injuries, the Kansas City Hyatt Regency walkways collapse left 114 dead and in excess of 200 injured. In addition, millions of dollars in costs resulted from the collapse, and thousands of lives were adversely affected [1].

The case taught several lessons, but possibly the most significant is the importance of collaboration.  According to the company contracted to construct the building, Haven, a call was made to the structural engineering firm, G.C.E., for change approval on an alteration to a connection. G.C.E denied receiving this call. This connection ultimately failed, causing some ambiguity as to who was actually liable. Additionally, the engineering firm, reportedly asked to have an onsite inspector for the project but this was denied by Haven due to cost.

The issues:

  1. Did the call take place and, if so, was it sufficient?
  2. Should Haven hold liability for declining G.C.E’s onsite inspector request?

Solutions:

  • The On-site Inspector

Arguments can be made for both sides here. G.C.E did explicitly ask to be represented onsite, which puts some blame on Haven for denying this request. Conversely, G.C.E. requested payment for this inspection. This was not a service to the construction team, it was a responsibility of the structural firm. GCE should have provided the representative free of charge.

  • The Call

The solution to the ethics of the call resides in the regulations surrounding change orders. Haven may have received verbal confirmation to make the change via a phone call. If that is the case, how the engineer that they talked to had the authority to give that confirmation? How did they know this representative was who he said he was? How did Haven know that the calculations were verified or that they even existed? Haven had no way of knowing these things.

The only reasonable way for Haven to obtain this proof is from an official and notarized change order.

Obtaining a change order was the responsibility of Haven. Without one, Haven was working in direct infraction of the most current plan set.

Three changes need to be made

  1. The construction code of ethics must be made to require contractors to work exclusively off of official and verified planets (within a degree of reason).
  2. The structural engineering erring code of ethics must be made to forbid firms from being careless with confirmations they provide.
  3. Legislation must be passed which strictly outlines regulations as to which forms of confirmation can be accepted.

 

Work Cited

[1] “The Kansas City Hyatt Regency Walkways Collapse.” ENGINEERING ETHICS (n.d.): n. pag. Tamu.edu. Department of Philosophy and Department of Mechanical Engineering, TEXAS A&M UNIVERSITY. Web. <http://ethics.tamu.edu/Portals/3/Case%20Studies/HyattRegency.pdf&gt;.

[2] Lowery, Lee, Jr. “Menu.” Zachry Department of Civil Engineering Ethics Site Case Studies Hyatt Regency Photos. TEXAS A&M UNIVERSITY, n.d. Web. 22 Feb. 2016. <http://ethics.tamu.edu/CaseStudies/HyattRegencyPhotos.aspx&gt;.

 

 

Design Proposal (in progress)

Introduction

Statement of the Problem: A prototype of a ukulele which can teach the user to play it has been developed. There are several issues which need to be addressed, such as improving usability and sound. The second model of this ukulele is in the planning stage. 

Purpose of Study: The purpose of this study is to provide a new interpretation of music education.  Ideally, the next model will provide a fluid and intuitive learning experience for users. This study will address the issues of the first ukulele model. The second model will address the following:

  • Creating a ukelele strong enough to use metal strings
  • Improving intonation
  • Implementing finger tracking
  • Writing code for the ukulele to react as it is played in either visually appealing or informative ways
  • Incorporating 3D printed parts for accuracy
  • Incorporating a text file read in for song storage
  • Designing an improved menu
  • Introducing SD card storage

 

Definitions:

All hereafter mentioned instrument parts are in reference to a ukulele, although they may be applicable to other instruments as well.

Adafruit: A Manhattan based electronics retailer. Designer of the NeoPixel.

Arduino: An arduino is a popular brand of microcontroller. It is open source meaning similar models can be developed by third parties. A 3rd party Arduino mega was used for the model 1.

Bridge: A wooden ukulele part which connects the strings to the soundboard of the ukulele. See Figure 1.

Fret: A piece of metal wire which lies on the fretboard. When a string is pressed down onto the fret, the length of string which can vibrate is shortened from its full length. This raises the pitch of the vibrating string.

Fretboard: A flat wooden ukulele component which lies on the neck and soundboard of the ukulele. It has systematically distanced frets to allow each string to play several different notes depending on where the string is pressed down. See Figure 1.

Headstock: The top of a ukulele. The headstock and neck are usually a continuous piece of wood. The headstock is the upper connection between strings and the ukulele. The headstock houses the tuners (or tuning pegs) for the ukulele. See Figure 1.

Microcontroller: A device used to control outputs and receive information through its I/O pins. These usually run on C or C++. Common examples include: Arduino, Raspberry Pi, Teensy, and the Trinket.

NeoPixel: An individually accessible RGB LED designed by Adafruit. Each LED has an integrated microprocessor. They can be strung together while still being individually controllable. Their compact size, high brightness, and combined use of only one output pin makes them ideal for this project.

Neck: A structural member of the ukulele. This member must be able to resist the tension of the strings and still rest comfortably in a ukulele player’s hand. See Figure 1.

Saddle: A component of a ukulele bridge, usually made of plastic or bone. It raises the strings to the appropriate height. See Figure 1

Soundboard: The faceplate of a ukulele’s body. The type of wood used for this part is an important component of the volume and warmth of a ukulele’s sound.

Soundhole: A hole on the soundboard of acoustic ukuleles. This is generally directly below the strings and located near the end of the fretboard. See Figure 1.

Trinket: A microcontroller designed by Adafruit. The pro edition is nearly identical to an Arduino Uno, but cheaper and much more compact. A Trinket will be used in model 2.

Tuners: Also known as tuning pegs. Devices used to change the tension in the strings by turning to wrap the string around a bar.

Figure 1

ukulele diagram copy

Image provided by get-tuned.com

 

 

 

 

Significance of the Study: There are several intended outcomes of this project. The first is the notion that motivated me to begin the first model: A ukulele with smart LEDs integrated into the fretboard would be really cool. The second outcome was stumbled upon during the coding portion of the first model: The ukulele could provide a new, intuitive, and affordable means for individuals to learn an instrument. Once the project is polished, it could be used both by individuals and in school systems.

Literature Review: Most of the design components for this project are well documented. Instrument quality improvements, such as attaching frets, will be implemented from professional procedures (Silberberg). Logic gates will be used to reduce the required microprocessor inputs. The process for using these is described in Design of Logic Circuits Using Reversible Gates (Manoj et al., 2014). The project will also address the structural necessities and intonation improvements. The necessary information for this is provided in The Science of String Instruments (Rossin, 2010). Additionally, text file read in and SD card implementation will be simple to implement in this project. These aspects are clearly laid out in Beginning Arduino (McRoberts). This project utilizes components from adafruit. Guides and datasheets for all components are provided (Freid, 2014).

 

Questions or Hypothesis: How can the first model be improved upon? How can these improvements actually be built into the ukulele?

 

Developing the U-lele Model 2

Working thesis:

Through developing a second iteration of the U-lele, it is possible to create a marketable device which is capable of teaching users to play the ukulele.

 

Working Arguments

  • Competitive with gTar
    • Multiplexing inspired input minimization
      • Less inputs=cheaper
    • Visual appeal
    • Iphone not required
    • Also appealing for performers
      • Free play mode*
      • Passive Display mode*
    • Only device designed around a ukulele (although future aspirations include branching out to other stringed instruments
  • MODEL 1 & 2 COST
    • Click here to see cost breakdown
  • Design Challenges include:
    • Creating a ukelele strong enough to use metal strings
    • Improving intonation
    • Implementing finger tracking
    • Incorporating 3D printed parts for accuracy
    • Incorporating a text file read in for song storage
    • Designing an improved menu

Questions List:

  1. How can production cost be further reduced?
  2. Will my Keyboard inspired finger tracking be efficient?
  3. What is the tension in each string?
  4. How can intonation be improved?
  5. What type of pickup is best?
  6. How can I store a text file on an arduino?
  7. How to eliminate noise from pickup?
  8. Is there a way to systematically convert ukulele tabs into U-lele songs?
  9. How can I better install the electronics into the ukulele?
  10. HOW TO DESIGN A MENU?

Methodology

Design Approach: This project is primarily an attempt to bring the ukulele closer to being a marketable product. This being the case, the design approach is heavily based around making improvements to the original model. This will be accomplished through troubleshooting and redesigning completed by myself. I will also be utilizing my colleagues and family to test the device and provide feedback. This adds no additional cost to the project. Funding for the project will be put towards material costs.

Type of Design Used:  A study with issues and solutions for the first model of the U-lele (name subject to change).

Role of the Researcher: Interviewer and designer.

Data Collection and Analysis: A combination of observations and interviews will be used. Individuals will be observed using the device (after being given varying degrees of instruction). They will then be interviewed to obtain feedback.

Ethics: Few ethical issues are raised by this project. Any substantial discoveries on the musical learning process should be made available to the public–however, the scope of the project suggests that no well founded discoveries will be made.

Reliability and Validity of Methods and Results: This research is intended to find any improvements which can be made between the model 1 and the model 2. All feedback is relevant and will likely be implemented if reasonable. Conflicting feedback will be evaluated. The small pool of data is of little concern for this stage of the model, but a more diverse pool would be useful for further development of the product.

Timetable: This design stage of the project is currently underway. The only current roadblock is funding for build materials. Once obtained, the build stage may commence. The model 2 will be completed by summer 2017 but may be available as soon as December 2016.

Resources and Materials:

  • Soldering supplies
  • Workspace
  • All necessary woodworking supplies
  • Misc Ukulele parts (see budget for more details)

Budget: Click here for full budget.

Limitations: There is a small sample pool for research. The model also is more expensive than a production model.

Delimitations: This model will be a second prototype, not a marketable product. The build and code both need to be improved before they can be solidified into final product. That being said, this model will have a soldered circuit opposed to a printed one.

Final: The findings that this project would provide would allow create a product that is nearly marketable. The sound, interface, and usability of the ukulele will all be polished.

Bibliography

Silberberg, David. “Pohaku Ukulele.” Kanopy. Les Blank Films, n.d. Web. 2 Apr. 2016.

<http://colorado.kanopystreaming.com/video/pohaku-ukulele>.

This video shows the entire build process of a ukulele. As this is done by a professional, many specialized machines are used. These are out of the scope (and price range) of this project. The principals of each step of the design, however, are still easy to follow and should be reasonable to replicate without specialized machines.

 

McRoberts, Michael. Beginning Arduino. New York: Apress, 2010. SpringerLink. Web. 29 Mar.

  1. <http://0-link.springer.com.libraries.colorado.edu/book/10.1007/978-1-4302-3241-4>.                                              

 

Michael Roberts, also known as “the arduino guy,” is a popular writer of arduino guides and tutorials. His book, Beginning Arduino, covers various Arduino topics. Chapter 15 covers reading and writing to an SD card. This will be used twofold in developing the next model. The more simple application will be implementing SD card storage. This will allow songs to be easily added to the ukulele. The other application is utilizing text files for storing the songs. This resource will be consulted for efficient methods of converting lines of text into a custom class for the ukulele.

 

“Introducing Pro Trinket.” Adafruit. Adafruit, 24 Aug. 2014. Web. 02 Apr. 2016.

<https://learn.adafruit.com/introducing-pro-trinket>.                                              

 

Limor “Ladyada” Fried is an MIT engineer and founder of Adafruit. In this article, she gives all the necessary information about the microcontroller used in this ukulele project. It contains all necessary programs, libraries, and specifications for implementation in the model 2.

 

“Adafruit NeoPixel Überguide.” Adafruit. Adfruit, 30 Aug. 2013. Web. 02 Apr. 2016.

<https://learn.adafruit.com/adafruit-neopixel-uberguide/overview>.                                              

Phillip Burgess, senior designer at Adafruit since 2011, is a popular writer for the Adafruit website.This is the primary resource on neopixels (a key component in both model 1 and 2). It covers the requirements, guidelines, and resources necessary to operate the neopixels.

 

Manoj, K.v, and M. Amarnath Reddy. “Design of Logic Circuits Using Reversible Gates.” IJETT

International Journal of Engineering Trends and Technology 16.8 (2014): 394-96. Web.

30

Mar. 2016.

 

This journal entry is available here. In order to reduce the necessary inputs to the device (as well as simplifying the code), a network of logic gates will be needed. This resource goes over their theory and implementation. It will be used in the design of the finger placement tracking system.

 

“The Science of String Instruments.” The Science of String

Instruments | Thomas Rossing | Springer. Ed. Thomas Rossing. Springer New York, 2010. Web. 02 Apr. 2016. <http://www.springer.com/us/book/9781441971098>.

                                             

Thomas Rossing is an accomplished researcher in several fields of physics and is employed by Stanford University. One of the major difficulties of this project is implementing metal strings. Ukuleles generally avoid this because metal strings require such high tension compared to nylon strings. They can tear the off the bridge of the ukulele or the soundboard entirely. This resource provides the information I will need to correctly analyze and minimize the tension in the model 2 strings. It also provides information to aid in the improvement of the ukulele’s intonation.

How to maintain a passion for engineering in college

Before I get into a long anecdote surround a quarter life crisis, I’ll go ahead and give the solution: join engineering clubs. If you just want to know about this solution, go ahead and skip down to Why things changed.

Why I needed a change

Studying engineering is hard, but also rewarding. As an engineering student, one of the hardest parts can be keeping your eye on that reward. In my studies, have come to two points where I wasn’t sure if I wanted to be an engineer. Two points where I was afraid that all my studies would lead a career that feels like a prolonged homework problem.

In both cases there was one clear causal factor: a lack of application. My first crisis occurred just over a year after my first projects course had ended. Since then, my studies had been exclusively theoretical. Then came a rather difficult school week, as can happen in engineering schools. In the midst of sleep deprivation, exams, stress, and lab reports, I couldn’t find it in myself to say that this is worth it. I would later realize that this was due to how little creativity I was being encouraged to use. For the time being, I sucked it up and trudged through my work. When the week was over, things went back to normal.

The second case was worse, a real quarter life crisis. I had had landed an fantastic internship that would eventually lead into my dream job. I shadowed my mentor to meetings for projects that genuinely mattered. I learned all of the bells and whistles of the business. However, as time passed I became less and less passionate. Eventually I abandoned the idea of working in this field entirely. In a panic, I changed my major to physics causing the least happy semester of my life.

I learned something about myself that semester. I had chosen to study engineering because I wanted to create. It wasn’t inherently engineering and my internship that had made me so unhappy. It was the lack of opportunity to apply anything that I had learned. I hadn’t created anything with my hard earned knowledge. I quickly realized that physics was the wrong field for me and moved back to civil engineering. Things changed for the better.

Why things changed

I joined a club! Two actually. If there is one piece of advice I can give to any college student, that’s it. By the time I joined, it was the second semester of my junior year, and until I then I had never applied what I was learning in college. Now that I’m finally getting to use what I know, I feel like these are the glory days. I have never been more content with my education.

I became mildly associated with CU Bridge to Prosperity and I’m looking forward to becoming more involved next semester. The club I really came to love, however, was the CU seismic design team–a section of the CU chapter of the Earthquake Engineering Research Institute (EERI).

The premise of the seismic design team:

  1. Design a structure that is
    1. Economically feasible
    2. Architecturally attractive and
    3. Most importantly, can withstand an earthquake
  2. Build a scale model out of balsawood
  3. Travel to an international competition where you
    1. Present your design
    2. Put your model through scale earthquakes and hope it doesn’t break

Shortly after me joining the club, we began construction. I was cutting and gluing balsa wood for hours every day. Each time I showed up, I left with some new bit of knowledge. The seniors on the team had picked up a thing or two outside of their courses and they were always excited to share them. This was one of the best factors of the club. Every time I glued a piece onto the building, one of its designers was there explaining what it did, why it was needed, and the theory behind it. That took place while I watched the building rise floor by floor for weeks until the glorious day it was finally complete. The build helped to re-spark my passion for engineering.

Although I had only recently joined the club, I was given the opportunity to be one of the members who traveled to this year’s annual competition taking place in San Francisco. From the plane taking off to the last minute in California, it was a wonderful experience.

We were always either preparing for the next phase of the competition or passing our time with and learning from students from around the world.  The Romanians and Stanford taught us about buttresses. Other schools shared their experiments with damping. Over the week I was in San Francisco, I compiled an extensive list of improvements we could use for next year’s structure. As it so happens, we would need them. Our structure collapsed on its last earthquake. While it was thoroughly disappointing, this is also an exciting event to explore. As next year’s design lead, I will be finding the causal factor in the collapse and guiding my team to fix it.

I finally love what I am doing. I spent too long, wasted too much time, letting my passions die out. I’m just thankful that I found a way to bring them back to life. If you are ever bored with your education, if you ever feel your interest in engineering fading, join a club. It just might change everything.

 

Solution to ‘The Brooklyn Bridge Bike Lane Disaster’ is a Disaster

 

By Cody Candler

Urbanophile blogger, Aaron Renn, suggested an improvement to the current layout of the Brooklyn bridge. Renn noticed an overcrowding of the public walkway that was, in part resulting from a bike lane which takes up approximately half of the promenade. Renn suggests that the solution is rather simple. He imposes that one traffic lane of the bridge should be converted into a bike lane.

Untitled

Proposed Bike Lane

Unfortunately, there are a  a few complications with this proposal:

  1. Safety of bikers
  2. Reduced traffic flow
  3. Lack of supporting evidence

Biker safety seems to not be a major concern of Renn, as the proposal is generally written to benefit conditions for pedestrians. His proposal would put a two-way bike lane directly beside heavy vehicle traffic. It seems entirely plausible that this could occasionally cause bikers to veer into a car lane.

The loss of a lane may also result in reduced traffic flow.  Ten or so major roads feed into each side of the brooklyn bridge. Especially during rush hour, a 33% in traffic flow in one direction this would cause a bottleneck which would not only slow down traffic on the bridge, but also throughout portions of either Brooklyn or Manhattan (depending on which side of the bridge is modified).

 
None of this necessarily says that Renn’s proposal is wrong. It does show that he needs further evidence to support his claim. He says that this is a simple solution, but its implications range much further than just moving a bike lane. So far, a photo (below) is the entirety of Renn’s evidence. If Renn wants this to become a reality, as I’m sure he knows, an in depth study and report on the impacts of the transition are needed.

 

50660a444c83b

Renn’s Evidence for Promenade Crowding

A College Student’s Stages of Identity

By Cody Candler

As someone whose sense of identity resembles Colorado’s sense of weather, I find it deeply comforting to know that the topic of identity is well-researched. In the article Eight Stages, Two Paths: Erik Erikson’s Psychosocial Stages Of Development, Rifka Schonfeld of the Jewish Press discusses the views of renowned psychologist and fabricator of the term “identity crisis,” Erik Erikson (below). Erickson stated that there are eight stages of our lives that determine

Erik-Erikson-Facts

Erik Erikson (1902-1994)

who we are. In the fifth stage, fidelity, “Adolescents, ages thirteen through nineteen, struggle with, ‘Who am I and what can I be?’” [1]. The sixth stage, love, “can happen anytime between ages twenty and thirty-nine and is usually capped off in marriage. The essential question is, ‘Can I love?’”[1].

 

This seems to model my experiences rather well. I was a twit of middle schooler, as many of us were. My personality could be accurately and completely summarized as wanting to be liked. I wasn’t involved in much drama and I wasn’t much of an antagonist but I was willing to change anything from my mannerisms to my taste in music to fit in. Then as I transitioned to high school, I saw myself develop into an individual. There were so many more people–I wasn’t afraid that I would be alone if I was an individual. Along with that came a personal sense of morals,

College followed a similar structure, but on a larger scale. When I was one semester into my college experience, I met a girl who I loved. My identity gradually became less self-focused. I’m now two years into that relationship. I’ve recently found that the best way to remember who I am is to spend some time with this amazing person.  I can’t validate Erikson’s other six stages of development, but I know fidelity and love describe me well.

 

 

 

[1] Schonfeld, Rifika. “Eight Stages, Two Paths: Erik Erikson’s Psychosocial Stages Of Development.” The Jewish Press RSS. The Jewish Press, 18 Sept. 2015. Web. 27 Feb. 2016.

[2] “10 Interesting Erik Erikson Facts.” My Interesting Facts RSS. N.p., n.d. Web. 27 Feb. 2016.

 

 

Why can’t the US keep up with international test scores?

By Cody Candler

Pew Research Center conducted a study on American attitudes towards the US educational system (2015):

Only 29% of Americans rated their country’s K-12 education in science, technology, engineering and mathematics (known as STEM) as above average or the best in the world. Scientists were even more critical: A companion survey of members of the American Association for the Advancement of Science found that just 16% called U.S. K-12 STEM education the best or above average; 46%, in contrast, said K-12 STEM in the U.S. was below average. [1]

Are these opinions justified? According to the 2011 Trends in International Mathematics and Science Study (TIMMS) results, our international standardized test scores don’t hold up against countries like Japan and Finland. Our PISA (Program for International Assessment) scores are even worse―ranking the US around the middle of the pack.

  • Math

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[2]

  • Science

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[3]

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[1]

Fortunately, as Pew Research Center points out in U.S. students improving – slowly – in math and science, but still lagging internationally [1], the U.S. is making progress. The article points out that our worse scores come from the PISA, which evaluates 15-year-olds across 64 countries. We fare much better on our TIMMS scores which evaluate 4th and 8th graders across 42 countries. This could indicate that our younger generation has been receiving a more effective education. The National Assessment of Educational Progress (NAEP) has observed an increase in math scores of American 4th and 8th graders since 1990 (right) [1].

 

 

Additionally, the 2011 TIMMS report officially listed the United States as an improving country in math for 4th and 8th grade and science for 8th grade; although, 4th grade science didn’t make the list [4] . Even if our scores aren’t the best in the world, the U.S. educational system is seeing improvement in standardized test scores.

  • Math
  • Science

Of course,whether standardized tests are beneficial at all is a heavily debated topic and the overall scores certainly aren’t the most useful information the tests give us. If anything is truly valuable, it is the breakdown of which questions are being missed.

On the TIMMS test, American students do quite well on questions that are fact based such as this 4th grade  science question:

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[4]

 

 

 

 

 

 

 

 

 

and this 4th grade math question:

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[4]

but our students are struggling with questions that require problem solving such as this 4th grade science question:

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[4]

and this 8th grade math problem:

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[4]

Unfortunately for the U.S., the ability to problem solve is generally much more useful that memorizing facts in STEM fields. The poor performance of the U.S. in these standardized tests means one of two things. Either the entire American education system is designed in such a way that our children aren’t getting an opportunity to problem solve OR our participation in standardized testing is encouraging ineffective methods of teaching. Either way, if the U.S. wants to get ahead in education internationally, increased problem solving skills are key.

Work Cited
[1] Desilver, Drew. “U.S. Students Improving – Slowly – in Math and Science, but Still Lagging Internationally.” Pew Research Center RSS. Pew Research Center, 02 Feb. 2015. Web. 13 Feb. 2016. <http://www.pewresearch.org/fact-tank/2015/02/02/u-s-students-improving-slowly-in-math-and-science-but-still-lagging-internationally/&gt;.

[2] Mullis, Ina V. S. TIMSS 2011 International Results in Mathematics. N.p.: n.p., n.d. Web. 11 Feb. 2016. <https://nces.ed.gov/timss/results11.asp&gt;.

[3] Martin, Michael O., Ina V. S. Mullis, Pierre Foy, and Gabrielle M. Stanco. TIMSS 2011 International Results in Science. N.p.: n.p., n.d. Https://nces.ed.gov/timss/results11.asp. Web. 11 Feb. 2016.

[4] Highlights from Timss 2011: Mathematics and Science Achievement of U.S.Fourth- and Eighth-Grade Students in an International Context. AppendixE: Standard Error Tables. Nces 2013-009. N.p.: n.p., n.d. Web. 11 Feb. 2016. <https://nces.ed.gov/timss/results11.asp&gt;.