Comparing methods of measurement: why plotting difference against standard method is misleading

My reasons for jumping into stats was to directly compare two measurement methods… with multiple trials, on multiple ILDs (inter-landmark distances).  I don’t really go for “funny name, lol” things, but when Bland and Borg are cited in the same paper on stats (which I long thought of [cluelessly/ignorantly] as boring).  Eponysterical.

But getting real, the issues raised by Bland and Altman sound pretty interesting, and they raise the issue that many tests of this sort may be using misleading information… I have tried to duplicate their methods in my own little H.T.-UGR/Inquiry Study.

 

 

Summary

When comparing a new method of measurement with a standard method, one of the things we want to know is whether the difference between the measurements by the two methods is related to the magnitude of the measurement. A plot of the difference against the standard measurement is sometimes suggested, but this will always appear to show a relationship between difference and magnitude when there is none. A plot of the difference against the average of the standard and new measurements is unlikely to mislead in this way. This is shown theoretically and illustrated by a practical example using measurements of systolic blood pressure.

Introduction

In earlier papers [1,2] we discussed the analysis of studies of agreement between methods of clinical measurement. We had two issues in mind: to demonstrate that the methods of analysis then in general use were incorrect and misleading, and to recommend a more appropriate method. We saw the aim of such a study as to determine whether two methods agreed sufficiently well for them to be used interchangeably. This led us to suggest that the analysis should be based on the differences between measurements on the same subject by the two methods. The mean difference would be the estimated bias, the systematic difference between methods, and the standard deviation of the differences would measure random fluctuations around this mean. We recommended 95% limits of agreement, mean difference plus or minus 2 standard deviations (or, more precisely, 1.96 standard deviations), which would tell us how far apart measurements by the two methods were likely to be for most individuals.

 

via Comparing methods of measurement: why plotting difference against standard method is misleading.

Screenhero | Collaborative Screen Sharing

Screenhero lets you screen share any application with anyone, no matter where they are. It’s super simple and blazing fast. You each get your own mouse pointer, and you’re both always in control. It’s designed for collaboration, not just broadcasting your screen. It’s like Google Docs for any application on your computer.

Screenhero is designed to feel like you’re sitting next to the person you’re working with — even when you’re miles away. It’s available for both Mac and Windows.

via Screenhero | Collaborative Screen Sharing.

SOPA! How it could destroy public intellectualism, and the furtherance of an educated, creative, developing society.

UPDATE: The White House has begun to respond to the protesting voices of American Citizens (ironically, united, but not by Citizens United) 

This is a list of sites taking action against SOPA on the 18th of January.

This post will be an updating one, currently I am just trying to collate information, links, and materials, as well as sources relating to the primary actors in this game… the politicians advancing such a dangerous, ignorant, reactionary and anti-modern, anti-liberty, anti-freedom based laws.

Currently, no ideas in this post are my own (for some digging I did on copyright a while back, check here), I will work to compose my own thoughts, but I thought that was completely secondary to linking OTHERS to the information to create a cogent case against such techno-phobic, corporately sponsored ignorance in our nations lawmakers.  I will note now only that SOPA is emphatically not “simply” a law to “stop piracy”… as written, it will break the internet.  I know many will already be aware of the issues presented, but consider that this is not simply a matter of “them foolish kids downloading the new hot Britanny Spears Track”… this law will DETRIMENTALLY impact the free flow of information between scholars, public intellectuals, and people who are hungry for rational, logical debate and information transmission.

If we wanted twitter to be censored, and to have our information fed through a blender that filters out anything negative about our government… we might simply go to China.   It is pathetically ignorant to, on one hand spew spittle flecked invective at “human rights abusing” China, and to sneer about how “Chinese citizens are not free, and do not have free thought or expression”… well, our distinguished “leaders” have decided that, hypocritically, that is what their vision of America entails.

The question to ask is; IS THIS WAR ON FREEDOM AND LIBERTY WHAT I WANT FOR MY CHILDREN?

“A growing tension between rights holders and libraries”

Butler mentions three copyright infringement lawsuits against universities and their libraries—the Georgia State e-reserves case, the AIME vs. UCLA video streaming case, and Authors Guild v. HathiTrust. “These lawsuits reflect a growing tension between rights holders and libraries, and some rights holders’ increasingly belligerent enforcement mentality,” Butler wrote. (On September 14, the LCA released a statement [PDF] in support of HathiTrust and its research library partners in the Authors Guild v. HathiTrust case.)

What can you do now?  The EFF offers this toolkit for anti-sopa activists;

  1. Call your Senators and Representative and tell them to oppose Protect-IP and SOPA, respectively.  Click here for some suggested talking points. Then tell your friends about the call on social media sites.
  2. Contact Congress through EFF’s action center.  Customize your letter to explain who you are and why you are worried about this bill. If you’re outside the United States, try this petition from Fight for the Future instead.
  3. If you work for a tech company, approach the leadership at your company and explain to them your concerns. Urge them to join you in speaking out. These companies (PDF) already took a stand.
  4. Write a blog post about the blacklist bills.  Whether it’s a candid explanation of why you oppose the legislation, a discussion of the effect on human rights, or a call to filmmakersto protest the blacklist, there are plenty of things to say about this scary legislation. Help us get the word out by writing articles on your own blog, your school blog, or on blogs that take guest contributors.
  5. Are you an artist? Showcase the dangers of censorship through art and music, and use your art as a way of reaching people who might otherwise not know about this issue. You can make stickers, posters or patches, create a YouTube video, or hold an open-mic night around censorship.
  6. Do you administer a website? Then put a banner on your site protesting censorship or link to EFF’s action center.
  7. Coordinate a teach-in or debate at your local college or community center. Invite local experts in copyright and free speech to come discuss the issue.
  8. If you’re in high school, talk to your civics and media studies teachers about a class discussion on the implications of this bill. Point them to our free Teaching Copyrightmaterials.
  9. If you’re in college, speak out through like-minded organizations working for digital freedom, such as Students for Free Culture or Electronic Frontier on Campus. If there isn’t a chapter at your school, start one. Then use that platform to coordinate with other students to speak out against this bill.
  10. If you’re in college, set up a meeting with your college newspaper editorial board and explain the bill to them and why they should speak out about it. Work with them to write articles on the topics. Check out these examples from the University of BuffaloUniversity of Massachusetts, and University of Minnesota.  See more examples at the Center for Democracy and Technology’s Chorus of Opposition page.
  11. Write a letter to the editor of your local paper. Remember, these are often really short. Find out the requirements for your local paper and follow them carefully.
  12. Become a member of EFF. We’re leading the fight to defend civil liberties online, so that future generations will enjoy an Internet free of censorship. By standing together, we can make it happen.

….

The Senate’s PROTECT IP Act and the House’s Stop Online Piracy Act (SOPA) are so noxious that even the Business Software Alliance has serious reservations, and SOPA’s main backer had to take to the virtualpages of National Review today to quell a growing revolt among his conservative colleagues about “regulating the Internet.” Whatever you think of the legislation, it unquestionably represents a sea change in the US approach to the Internet, one which explicitly contemplates widespread website blocking and search engine de-listing.

The level of debate on an issue this important has been… suboptimal. (And hearings have been rather lopsided affairs). Just listen to the rhetoric of SOPA author Lamar Smith: “Enforcing the law against criminals is not censorship.” Pithy, sure, but it doesn’t relate to any actual objections put forth by thoughtful critics.

But rightsholders do need some means of enforcing copyrights and trademarks, something tough to do when a site sets up overseas and willfully targets American consumers with fake goods and unauthorized content. Some sites can be leaned on when hosted in friendly countries, but many simply thumb their nose at US law with impunity. If you can’t go after the sites at the source, and you can’t lure their operators to the US (both tactics used with success in other cases), what’s left but blocking site access from within the US?

(Via:ARS-Technica)

OPEN: Online Protection & Enforcement of Digital Trade Act

The OPEN Act secures two fundamental principles. First, Americans have a right to benefit from what they’ve created. And second, Americans have a right to an open internet. Our duty is to protect these rights. That’s why congressional Republicans and Democrats came together to write the OPEN Act.

….

One of the many serious problems with the Stop Online Piracy Act (“SOPA”) (pdf) is how it tacks itself onto existing law to expand liability to people who may be three times removed from any actual copyright infringement. In § 103, SOPA wraps another layer of liability around what are called the “anticircumvention provisions” of the Copyright Act (which are found in section 1201 of the Copyright Act). The goal of the anticircumvention provisions is preventing people from circumventing technology that protects copyrighted works. Importantly, however, some courts have held that § 1201 prohibits circumvention even when the person’s ultimate use of the work does not infringe copyright. So if you circumvent technology to access a work in a way that’s completely legal, you might still be violating § 1201. If SOPA is passed, even more individuals and entities will get caught up in an ever-expanding net of liability, which is especially ridiculous when we’re talking about a provision of the law that may not even require actual copyright infringement.

SOPA’s Ever-Expanding Net of Liability


Earlier this week, the Library Copyright Alliance (LCA)—made up of the American Library Association, the Association of Research Libraries (ARL), and the Association of College & Research Libraries—released an open letter [PDF] to Sen. Ron Wyden (D-OR), Rep. Darrell Issa (R-CA), and Rep. Jason Chaffetz (R-UT), “welcoming [the] release” of a discussion draft bill the legislators have sponsored. Called the Online Protection and Enforcement of Digital Trade (OPEN) Act, the bill has been touted as a potential alternative to SOPA.

Though SOPA [PDF] is primarily aimed at combating copyright infringement by foreign websites, many observers have taken issue with the enforcement methods described in the bill, which could have far-reaching effects—including in the library world. (Yesterday, 83 Internet engineers and inventors wrote an open letter to Congress saying that SOPA and similar legislation “will create an environment of tremendous fear and uncertainty for technological innovation.”)

On November 8, Brandon Butler, ARL’s director of public policy initiatives, wrote another open letter on behalf of the LCA criticizing two provisions of SOPA’s Section 201. One of them, he wrote, could expand the definition of “willful” copyright infringement to potentially include cases where a person (or organization) believed in good faith that its infringing conduct was lawful; such “innocent” infringement carries much smaller potential for monetary penalties than willful infringement does. (“In cases of willful infringement, the court can increase the statutory damages to $150,000; in cases of innocent infringement, the court can reduce the statutory damages to $200,” Butler wrote.)

Brandon Butler, Director of Public Policy Initiatives, at ARL talks SOPA with CNN’s Brian Todd.

Direct to Video Interview (via ARL Policy)

What’s Wrong With SOPA?

Apple Charts a Course for 3-D Maps – Technology Review

Apple Charts a Course for 3-D Maps – Technology Review.

Ever since the iPhone first came on the scene in 2007, Apple has been dependent on Google Maps. But there have been hints that Apple, at least since 2009, has been planning a rival service. In that year, it bought a mapping company called Placebase; last year, it scooped up a 3-D mapping company called Poly9. This week, 9to5Mac confirms that Apple has now purchased a third mapping company, C3 Technologies, which mysteriously shut down in August following its acquisition from a then-unnamed buyer.

 

 
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