Ellie Asks Why Annex

Mild science, tech news, stories, reviews, opinion, maps and humor

21 May 2018

Credibility and the Internet: Queuing Theory

Don't believe everything you read on the Internet!

This was old news about queues back in 1985. Yet it was written up as a journal article, and received coverage as though a new finding in the June 2010 issue of ScienceDaily, an online publication owned by Reuters.

M/M/1 queues, Kendall notation, and balking rate models are certainly useful. However, the concepts, and their accuracy as models, were well-established for at least forty years. This is true whether applying queueing theory to modelling the performance of computer hard-drives e.g. random arrival times for seek requests, or to consumer behavior when switching lanes because of long lines at the supermarket checkout.

The Wiley text book, Fundamentals of Queueing Theory, was published in 1998.

Earlier editions were published in 1983, and explain in detail the theory and application of the concepts presented in the journal article reviewed by ScienceDaily.

A little more about M/G/1

On Math StackExchange, I noticed a rare inquiry. If you're curious for more about queues, go read my answer to this question, Kendall notation's “General distribution”, what does that mean?

I found this comment endearing:

Oh I thought that this stuff wasn't even used in real life jobs... I thought it was merely theoretical, but seems that I'm wrong!
I'm okay with the G general theory [G as the general case when you just don't know what sort of service time distribution to expect] since I'm not required to study it for now (I'm following an academic course), I just wanted to understand what the G meant and you helped me in that. Do you have any experience with multi-class queues too?

Journal Reference
  1. Liao et al. "Optimal staffing policy for queueing systems with cyclic demands." International Journal of Services and Operations Management, 2010; 7: 317-332.

20 May 2018


Aluminum Necklace circa 1950
 0.75 in x 6.25 in.

EDIT Sadly, the Chemical Heritage Foundation was absorbed by Science History Institute between 2015 and 2018. You can still read about the illustrious past of the Chemical Heritage Foundation here. I will try to find new source links for the inline URLs below.

The aluminum necklace was on display at the Chemical Heritage Foundation (CHF). A description of the exhibit is still available from an image-free post on Atomic Age jewelry.

View additional wonders from the "Chemistry and Fashion: Making Modernity" via Exhibits | Chemical Heritage Foundation.  Non-electronic viewing is possible too! This exhibit and much more is accessible to the public at the CHF Museum on 315 Chestnut Street in Philadelphia, Pennsylvania.

Interested in the legacy left by Gordon Moore and his famous observation about the growth of technology? Read the original publication that introduced Moore's Law, Understanding Moore's Law: Four Decades of Innovation, Chapter 4, edited by David Brock.

magazine cover
The former CHF publication,
"Periodic Tabloid"
(Musings on the Molecular)

I'll provide one more chemistry related-link, about Professor A. Geim, winner of the 2010 Nobel Prize in Physics. In the span of ten years, he went from winning an Ig-Noble prize for levitating frogs with magnets to the Nobel Prize for introduction of the extraordinary carbonate graphene.

*Professor Geim is actually a chemist, not a physicist.

21 January 2015

Cartography of Second Life

Surprise! Cartography enthusiast and mapping patron David Rumsey was there too: Viewing Second Life.

Ellie with radio in SL
I am Ellie Heartsdale. I owned a small corner plot of land on an island sim in the west. I built a little house there, for me and the piggies. I went to the Second Life synagogue, in Nessus, on Friday nights.

Second Life animals

My father was still alive then. I was working for the State of Arizona, Department of Health Services, Office for Children with Special Health Care Needs, as chief research statistician. That was my title, "Research Statistician, chief".

I was happy, but as usual, didn't realize it at the time.


31 July 2014

Cassandra Is Sooooooo Correct

Nihon Cassandra is more of a stock market investor than macroeconomics type. In other words, she isn't really into bonds. In her own charming words,
So long as my distribution is skewed-right, and the tail not overly kurtotic, I am sanguine.
Recently, Cassandra excoriated herself for failing to predict our current global macroeconomic malaise, specifically, the odd lack of self-preserving behavior by those who have the most to lose. I think she is being unnecessarily harsh, as she understands far better than many others do, even now.

It was a close call. From September 2007 through 2010, the masters of financialization escaped ruin by the skin of their teeth. Saving the system, at public risk and expense, was useful to asset holders, e.g. the AIG crowd, Goldman Sachs and friends, Stevie Cohen, Walmart family scions, Icahn, Einhorn, Pritzkers, Koch brothers, Larry Ellison, Larry and Sergei Google, Mark Z, Jeff Bezos, Bill and Melinda, other much less publicly known owners of nation-sized yet privately owned wealth.

03 June 2014

If he were a spy

I looked for answers on Quora, a question-and-answer website.

Is Jacob Appelbaum a U.S. government employee?

He gets a huge salary from the Tor Project but mostly jets around the world, more lavishly than celebrities and movie stars. His home is chic, minimalist but opulent according to Rolling Stone. He posed with semi-automatic firearms in Iraq in 2008. He parties ALL the time, based on his flickr photographs. [These photos are no longer visible other than to logged-in flickr users with adult content viewing enabled. I embedded a few as part of my question on the Quora website and question comments.]

The question doesn't really seem to follow from the details, Ellie?

Granted, but maybe this will help to explain. Tor is a former US government project. Jacob works, or worked for Tor. I was trying to avoid asking directly whether Jacob were a spy. That would be indiscreet, so I said "US government employee" instead.

Jacob has more fans and cart blanche globally than, well, I don't even know who to compare with him. He is like the Larry Ellison or Eric Schmidt of crypto fandom, but without any visible means of support. I don't see his name on the cryptography research server IACR as an author, nor any ACM nor IEEE scholarly journals, not even the Financial Cryptography conference.

ioerror is, well, to make an analogy, like the subversive version of Google's Jared Cohen. ioerror is the cool kids' hero, so to speak.

23 May 2014

Message of the market

Joe Saluzzi tried to get the word out. He really did make a good faith effort. This was one of his numerous appearances on Bloomberg, Fox Business News, CBS etc. The mainstream news media did not ignore him. He was interviewed for about 10 minutes in each station's Manhattan studio. Each appearance was broadcast live. Receiving that much air time is unusual.

13 May 2014

The Cleveland Fed Drawing Board goes silent

I find Cleveland to be the most friendly of the 12 Federal Reserve districts. They do a lot of community outreach work, and have a good research department.
    Evidence of friendly Cleveland Fed!

The Federal Reserve Bank of Cleveland is the headquarters of the U.S. Federal Reserve System's Fourth District. The district is composed of Ohio, western Pennsylvania, eastern Kentucky, and the northern panhandle of West Virginia.

Fed Reserve building in Cleveland, Ohio
Main office in downtown Cleveland since 1923

The Cleveland Fed building was designed by architects Walker & Weeks. The building is considered an historically significant piece of architecture. I like how it looks too. Apparently, few know much about the art and architecture of the building, not even in Cleveland!

24 November 2013

Bitcoin in the limelight: Questions for buyers and investors

DDoS attacks manipulate vulnerable markets

The vulnerable market was the Mt. Gox Bitcoin exchange. In April 2013, Mt. Gox was overwhelmed by DDoS. The point, the company speculated, was to destabilize Bitcoin and fuel panic-selling. After driving market prices down, the attackers can then rush in and buy Bitcoin at the lower price. Obviously, this isn't fair.

Life isn't fair but Bitcoin must be

Life may not be fair in general, but securities and currency markets require fairness and avoidance of market manipulation in order to function. Without it, they will die. Trust is essential. Apparently, Mt. Gox was robust enough to withstand this volatility. The attackers were fortunate. In their pursuit of unfair profits, they are taking a selfishly short-term view. DDoS attacks could destabilize Mt. Gox, or any other entity that serves a similar purpose. If that happens often enough, or in sufficient size, it will undermine credibility in Bitcoin.

Mt. Gox wasn't uniquely vulnerable. In the past few months, there were other DDoS related Bitcoin extortion incidents. BTC-China was brought down in September 2013, and BIPS, a European payment provider, experienced a DDoS attack two days ago, on 26 November 2013.

27 October 2013

Paleo specie

This is BB Billosaur, a ceramic piggy bank for paper currency. He is made by Le Mouton Noir & Co. Le Mouton Noir is located in New York City. I am not surprised (I miss it there).

The store owners describe their motivation:
For many years we have followed the heard like a flock of sheep. Working hard, learning and growing, we have never let go of our dream. The black sheep finally wakes up and steps forward to have some fun.

Meet bb billosaur a ceramic piggy bank

BB Billo seems difficult to resist: A paper currency-only porcelain piggy with holes down his back emulating a Stegosaurus-like Mohawk, made by black sheep!

25 October 2013

Account hijackers

If a message originates from a familiar name or email address, its likelihood of making it through spam filters is greater.

Google described their efforts to minimize harm to users due to email account hijacking:
"Our security team...saw a trend of spammers hijacking legitimate accounts to send their messages. [We developed] a system that uses 120+ signals to...detect whether a log-in is legitimate, beyond just a password."
Less than 1% of spam emails make it into a Gmail inbox.

chart Google Gmail accounts compromised since 2010 decreased to nearly zero
Legitimate Gmail accounts blocked for sending spam versus time

The number of compromised accounts decreased by 99.7% since 2011. That's impressive, for a sustained reduction! How does Google avoid false positives? I am so curious about the specific details of their filtering rules!

The blog post was written in March 2013. It is remarkable that the same methods continue to be effective, as Gmail spam-attackers would perceive this as a new challenge to be overcome.

120 Signals

I suspect that Google's methods are analogous to those used by the U.S. Department of Health & Human Services' Centers for Medicare & Medicaid Services (CMS) in detecting medically unlikely edits (MUEs). MUEs can be accidental, due to claim coding or data entry errors. MUEs can also be deliberate, when there is fraudulent intent, e.g. by filing for more services, or for more expensive services. Regardless of intent, MUE identification reduces paid claims error rates.

How will the Affordable Care Act impact existing processes for detecting MUEs, and for setting benchmarks? CMS does not disclose its MUE criteria for the same reasons that Google will not reveal details about their 120 signals.

Continuous improvement is a part of life, for email-spam account hijackers, Google and the fraud detection team at the Centers for Medicare and Medicaid Services.

I wrote a post about health care, with a much more Ellie-centric theme, a few years ago. That was when I worked as statistician for ACCCHS, Arizona's state-administered Medicaid/Medicare program, monitoring program performance and quality of care.