It is very rare that a Blog Wyrm publication date coincides with the holy day of Good Friday.  World-wide, this day invites all of us to recall how an innocent man willingly endured death in order to save everyone else.  And while Christmas is important because it heralds the beginning and Easter is even more important because it demonstrates the victory, Good Friday should help us understand that sometimes there is a lot of pain to dealt with in between and that we should never lose hope.

One of the most enduring methods used for time series analysis is the family of real time estimation and prediction methods based on the Kalman filter.  Proposed by Rudolph Kalman in 1960, the filter algorithm that bears his name finds itself in a wide range of applications as well as a wide range of variations based on need.  Aristotle2Digital presents the basic algorithm in its original setting of a linear system of equations as a starting point for more involved future explorations.

Milton Friedman, when addressing a young woman, visibly distressed by the professor’s logical demonstration of the counterproductive aspects of equal-pay-for-equal-work laws, famously said “I’m on your side but you’re not.”  CommonCents shows how a similar situation applies to the city of San Francisco, even as it’s starting to recognize some counterproductive aspects in its own economic legislation, that has made it it’s own worst enemy. 

In some systems, like the solar system, the specific interactions between constituent parts are key to understanding its behavior.  In other systems, such as a glass of water, only large scale collective interactions matter while the specific details of the one-on-one interactions don’t.  But in critical phenomena, such as a phase transition in water, it is an interesting observation that the system in question exhibits aspects of each extreme.  UndertheHood, using some simple numerical experiments, shows how all length scales seem to be present near the critical probability in the percolation model.

Enjoy!

Wikipedia defines social engineering as:

And those of us who work in and around information technology (which is almost everyone) are routinely required by our employing institutions to take training in recognizing how to spot and thereby avoid the scams that come with many of the social engineering attempts we see across the internet such as phishing.  We learned to accept and live with the fact that scammers routinely attempt to manipulate us – in short to con us. 

But curiously, very few of us are willing to admit that conventional media, advertising, and social media would ever stoop so low as to manipulate us.  Of course, their approach isn’t as coarse and, for that matter, honest as a Nigerian scam, where the con artist simply wants the mark’s money.  Our modern scam infrastructure aims higher or lower.  The following quote, taken from Chapter 1 of the book Propaganda by Edward Bernays, the father of modern public relations and advertising puts it this way:

Makes one wonder as to who is doing the real social engineering.

Now onto the columns.

The famous movie, The Good, The Bad, and the Ugly had a running joke about there being two kinds of people in this world: people at the end of rope and the people who do the cutting or the people with loaded guns and those who dig.  This month’s Aristotle2Digital looks that the two kinds of people in this world who look at times series data: those who analyze what has passed and those who are looking at the data real time.  The techniques of the moving average and the exponential smoothing are contrasted against each other as useful tools for those two types of analysts.

There is something that seems to be lost in the recent controversy over In-N-Out burger announcing its one and only shop closing ever in Oakland.  On one side are those who believe enough is enough and In-N-Out should be able to leave with no strings attached (call them the laissez-faire crowd).  On the other side there are those who maintain that the closing is a cynical move on the part of a big corporation that simply didn’t see enough profit and is using ‘crime’ as an excuse to cut ties with a marginalized community (call them noblesse oblige crowd).  What CommonCents points out is that while everyone is focused on which of these two crowds’ perspective is right nobody seems to be pointing out the laisse-faire attitude the government has to their own noblesse oblige to keep crime down and provide opportunities to those who are underserved.

The old saying “the whole is greater than the sum of the parts” is apropos of the collective phenomenon of phase transitions.  Familiar forms of phase transitions cover the melting of ice to water or the boiling of water to steam.  This month’s UndertheHood looks at a simple but physically relevant model of phase transitions called percolation.  Despite its simple rules, the percolation model exhibits some surprising collective behaviors.

Enjoy!

A common theme at the start of any new year is the resolution.  Learn a new language, lose weight, exercise more.  As a society we value making resolutions, it seems, a lot more than we value keeping them.  So, as we start 2024, the Blog Wyrm staff is gratified to point out that our resolution to produce new content has now entered its tenth year.  And while there were some months where we faltered when life inevitably got in the way or some others where we took a well-deserved break we’ve, nonetheless, kept up our resolution.  Not too shabby.

Now onto the columns.

To quote Ecclesiastes, for everything there is a season.  And indeed, the real-world is teeming with phenomena that show trends and seasonal variations: the weather, home sales, catching a cold, etc..  In this month’s continuing examination of time series, Aristotle2Digital presents a simple look at the Holt-Winter trending and prediction algorithm.

Just when you think the governmental mess in California can’t get worse, the gang in charge of that state show that they have yet another card, drawn from the deck of unintended consequences, up their sleeve.  As CommonCents explores, this time the fast food workers are squarely in their crosshairs ready to have their economic livelihood shot down by a well-meaning law.

It’s hard enough to understand the radii of convergence of series expansions of real-valued functions.  It is another level of difficulty in understanding series expansions for operator-valued ones.  This month, UndertheHood takes a ‘experimental math’ approach to exploring when an operator can have a small-enough piece that a formal inverse expansion can converge with a finite (and reasonably small) number of terms.

Enjoy!

It’s been some time since we’ve take a break from publishing content but this month we at Blog Wyrm have decided that a little down time with family would be welcome. See all of you in the new year.

It is a Blog Wyrm tradition to remind ourselves, during the month of November, of the real significance of the Thanksgiving holiday.  Usually, we note that it was the dissolution of communal farming in the Pilgrim community and the adoption of private ownership that led to the years of plenty.  But this year, we’ll also point out that it was that same ideal of personal ownership, compounded many times over, during the decades since the watershed event, that has led to the achievements that has brought the world the wonderful standard of living it currently enjoys.  As our poster child of exceptional achievement, we’ll note that it was during this particular month of November that the Lucy mission had a close flyby of the Asteroid Dinkinesh.  While the planetary science of the mission is important, far more important is the way of life that led to the mission being proposed, built, and flown.  It is for that way of life that we should all be thankful.

Now onto the columns.

To paraphrase a famous running joke in the western The Good, The Bad, and The Ugly, there are two kinds of people in this world; those who want to know everything available before making a decision and those who just jump in.  And there is a lot of debate surrounding which strategy works best.  Clearly dealing with events as they come to pass is an important skill for any agent, be it natural or artificial.  Aristotle2Digital embarks on a new study of various strategies a rational agent might employ in analyzing time series data as it becomes available.  First stop is sequential statistical estimation.

There is a fundamental reason why economists look at the incentives built into any piece of legislation or policy.  It is because people always find rational ways of working their own self interest into whatever new rule is thrust upon them.  As CommonCents shows, the failed gun buyback program of the City of Oakland is one such case.  The city spent millions thinking its new program would make it harder to prevent gun crime only to find that when executing it they made a gun market bonanza where sellers could unload guns they couldn’t move otherwise and where sellers had a chance to find merchandize they wouldn’t have found otherwise.  Well, at least they tried.

The concept of an operator proves itself to be useful in quantum mechanics, general relativity, and a host of other physical applications.  However, the mathematics of operators can often seem obscure and inscrutable.  UndertheHood delves into how certain operator inverses can be formally built out of a certain infinite series with far greater ease than at first might be thought by simply following the same  steps one follows when dealing with functions of simple numbers.

Enjoy!

We at Blog Wyrm really wish everyone Happy Halloween, but it is difficult to be happy when so much of the world is swirling with violence and stupidity.  Nonetheless, even if we can’t feel particularly mirthful we can, at least, remind ourselves that life, while ugly at times, is a great gift and that the nobleness of the human soul allows for light to shine through even in dark times. And, after all, isn’t that really the point of Halloween?

Now onto the columns.

Is mankind a smart ape or a material reflection of a higher power?  What makes the species special?  And we are special as even the most pessimistic or nihilistic of us would concede.  Why else be pessimistic or nihilistic towards mankind but nothing else if you don’t tacitly assume humans are special.  This month’s Aristotle2Digital explores, in a very small way, some of the positions and points of view on the measure of Man.

Human beings, by their very nature, are storytellers.  Some stories mold and shape us, giving us role models and solutions to life’s ups and downs.  Some stories amuse us and tickle the bored recesses of our life.  But some stories harm.  These are the ones with a lie at the center and poison oozing out to the edges.  Such lies mislead us and seduce us into making terrible decisions.  CommonCents examines one such lie that is poisoning many minds these days: that the wealth of the developed world comes by theft from poorer countries.

The power of the Boltzmann equation is finally on full display in this month’s UndertheHood.  In this final installment for kinetic theory, the linkage between the mechanical degrees-of-freedom on the kinetic scale with the average field properties that manifest on the macroscopic scale comes full circle with the derivation of the fluid equations of motion.  A clear correspondence results between the random, disorganized motion of individual particles with the macroscopic behavior of the stress tensor.

Enjoy!

The transition from summer to fall has been surprisingly fast this year.  Of course, the actual astronomical transition took place as always with Earth’s slow and steady progress from the summer solstice to the autumnal equinox.  No… what we mean by ‘surprisingly fast’ is that the mood of the country moved rapidly from summer-time fun to back-to-school serious over a very short period of time.  It seemed that society was ready to put summer away quite quickly, even before Labor Day.  The weather largely cooperated with this speedy shedding of summer frivolity.  Perhaps it is the economy or the politics or the starting of the football season or whatever.  Speaking of surprises and football, it is worth noting that the Detroit Lions are surprisingly good this season; and we don’t simply mean good in the four-weeks-into-the-season unheralded success followed by the regress-back-to-the-mean mediocrity.  The Lions look like they have the makings to be a good team this year, but we’ll see in another 3 weeks.

And now onto the columns.

Things are not always what they seem.  This is a common theme in stories about not judging a book by its cover.  It should also be a theme when working with raw data.  This month’s Aristote2Digital looks at a generalization of the Z-score designed for multi-dimensional data sets with correlated data, called the Mahalanobis distance.  The Mahalanobis distance is particularly useful is peeling away the cover of the book to find out how things really are.

Counterfactual conclusions are hard to deal with.  How can one prove the claim that ‘If only this one thing would have been different the whole course of subsequent events would changed’.  Nonetheless, this seems to be the province of the social scientist and the economist.  And few topics provide a more polarizing landscape for counterfactual argumentation as does the national debt.  CommonCents looks at the debt history and both sides of the current debate over spending.

The genius of Ludwig Boltzmann shines no brighter than in the equation of kinetic theory that bears his name.  Sadly, that genius was not recognized in his own life perhaps because he was too far ahead of his time.  This month’s column in UndertheHood looks at a process by which the Boltzmann equation can be coaxed into reproducing the equations of fluid mechanics through a specialized averaging process.  This method provides enormous insight into how nature works and, perhaps, may have persuaded more of his contemporaries to embrace his ideas had it been more widely known.

Enjoy!

As August rolls to an end, there are many things to prepare for such as the beginning of the football season, the return of students to school etc.  One thing that we can’t prepare for is the new season of television due to the writers’ strike.  We at Blog Wyrm tend to be singularly unaffected as we don’t watch television – at least not the modern incarnation.  We’ve been working our way through various shows from the late 1990s and it is interesting to see just how things changed after 9/11.  Characters were written uttering such lines as “things will never be the same” and “we’ve lost a certain security that we’ll never get back”.  These lines may have sounded sincere and felt poignant at the time but there is simply no way that anyone can deny that for the most part, we no longer remember 9/11.  Much like Pearl Harbor, we can conjure up memories and say it was a dark day, but its shadow no longer seems to darken us, its horror no longer stains our psyche.  And that is all for the worse.  We should remember 9/11 and the fascist roots of control that grew yielded the 19 strange fruits that harmed us that day.  We should remember that desire to exterminate and see its cousins in many of the authoritarian dictates and dictators that have come after from the housing crisis, where ‘experts’ leveraged garbage into phantom profits and almost took down much of the global financial markets, to the pandemic with its hysteria and paranoia, to the cancel culture and perpetually offended class that lurks in every nook and cranny of social media.  We need to remember 9/11 if for no other reason than to remind ourselves that some of us are not so different than the people who carried out that massacre and that we need to remain eternally optimistic, charitable, and vigilant.

Now onto the columns.

Picture if you will an argument as old as time: Ty Cobb was the greatest baseball player.  Are you crazy, Babe Ruth is head and shoulders better. While there is never going to be a final way of settling arguments like these, the Z-score, as Aristotle2Digital shows, at least offers an unambiguous way to statistically compare players (or anything) in an apples-to-apples manner.  

When the word ‘economics’ is used in polite economy there is usually a sharp intake of air through many mouths as concerned looks immediately populate sets of eyes around the speaker.  Clear indications that the word might as well be spelled with four letters.  Nonetheless, CommonCents demonstrates that the content of economics thinking makes for great entertainment that is safe to talk about at any party.

Early in his famous ‘Feynman Lectures on Physics’, Richard Feynman ponders if all civilization were wiped out and only one nugget of learning passed on from the old to the new what should that be.  He asserts that the most useful idea to help the survivors rise from the ashes would be the notion of the atomic nature of matter.  UndertheHood looks at the some of the math behind that idea by presenting the Boltzmann equation which links the mechanics of the atomic picture with the macroscopic world.

Enjoy!

We at Blog Wyrm thought we would build on the theme from last month’s intro column, which was on the Beauty and Hope of Summer.  As we’ve been poking around in an outside world that has largely gone back to business as usual, it is gratifying to see how many beautiful, natural events serendipitously presented themselves to us.  Creation and providence are communicating to us all the time if we just take the moment to listen. 

Take for example this photo of the sunrise over the Atlantic Ocean.  The ocean and the sun, of course, move quite slow in human terms and, while lovely, provide little in the way of a surprise but note how the seagull quite kindly provided the dynamic silhouette that provides that special pop.

Likewise, clouds, sky, and the setting sun are common enough but rarely do they conspire to produce a backlit light show just after a set of thunderstorms as was captured below. 

So, we recommend that all of us put down our manmade distractions from time to time and enjoy what is really worth enjoy.

Now onto the columns.

A human being, regardless of how ‘smart’ or how ‘dumb’, has an amazing capacity for intelligent behaviors.  One of the most profound behaviors, and one almost always taken for granted, is the power of speech.  Not just the ability to syllabify without sounding like those electronic voices from electronic toys of yesteryear (yes, Speak-and-Spell, we’re talking about you) but the real talent to convey and understand meaning.  The Winograd Schema provides a set of sentences whose meaning is quite easy for even the most clueless of us to get while providing a stiff challenge for artificially intelligent systems.  Come and join Aristotle2Digital in exploring this interesting intersection between human speech and cognition with natural language processing and machine learning.

To paraphrase The Long Dark Tea-Time of the Soul by Douglas Adams: it can hardly be a coincidence that no language on earth has ever produced the expression ‘as smart as a politician’.  Some are stupid.  Some are very stupid.  Some attain a degree of stupidity that can only be the result of a special effort.  Case in point: the state legislature in the golden state of California.  As this month’s CommonCents details, through a variety of special efforts the public servants of Sacramento have managed to produce an economic environment perfect to screw over the new home buyer.  Two of the state’s biggest home insurance policy providers, State Farm (largest) and Allstate (4^th largest) are no longer accepting new home owners policies while other insurers are limiting the ones they provide – all because of a variety of measures designed to protect the home owner.

Computing a theoretical model is one thing, putting the theory into dynamic action with a simulation is entirely another.  This month, UndertheHood takes the hard sphere dynamical theory developed within the context of classical statistical mechanics and extends it to a simulation.  Along the way, an additional set of considerations, falling within the realm of computational physics, are developed for handling a world in finite time steps.  The resulting time evolution allows us to visualize how an out of thermal equilibrium thermalizes into the Maxwell-Boltzmann distribution and, once reached, how it fluctuates around the equilibrium.

Enjoy!

Despite pandemics, political upheavals, economics downturns, and domestic unrest and wars abroad, the seasons progress whether we like it or not.  The summer of 2023 is shaping up to be a beautiful season and it has been offering us breathtaking examples of the handiwork of God.  The Blog Wyrm staff just managed to get this breathtaking shot of a cloud bank near the horizon, back-lit by the setting sun, with rays of Buddha akimbo.  A reminder that there is always hope and beauty in the world.

Now onto the columns.

There is a well-worn maxim that states that everything old is new again.  Usually applied to fad and fashion, it apparently also applies to algorithms.  Case in point, the Hoshen-Kopelman algorithm, which was invented to assist in the investigations into physical percolation is now considered a type of machine learning algorithm.  Well, it isn’t clear that that label really applies but nonetheless, as this month’s Aristotle2Digital shows, this deterministic clustering algorithm, clever though it may be, still falls far short of what the human eye can do. 

Labor v. management.  It’s a drama as old of the hills but that kind of drama takes on a new life when the labor is the Writers Guild of America (WGA) and the management is the Alliance of Motion Picture and Television Producers (AMPTP).  Is it David versus Goliath or more like the affluent upper middle class against the wealthy upper class?  Who can say? But CommonCents can say just what the WGA is demanding and what the AMPTP is not saying and how various forces of economics are colliding in this fight.

There is a certain elegance to simple rules creating unexpected behaviors.  This is the charm of cellular automata and statistical mechanics and nowhere is this more on display then in simple simulations that demonstrate how analytically tractable scattering processes amongst hard spheres, when applied to randomized collection, inevitably leads to the Maxwell-Boltzmann distribution.  This month’s UndertheHood lays the theoretical ground work for just such a simulation.

Enjoy!