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Principles of Economics: Microeconomics

Understand the economic way of thinking.
Roman Hardgrave: Take the exam and submit your questions to &qu… more

The comparison between a pollution tax and pollution trading nee…
JAN 24
Principles of Economics: Macroeconomics

Economic growth, business cycles, monetary policy, fiscal policy, and more.
Mary Clare Peate: You asked, we answered…. more

The Puzzle of Growth
Everyday Economics

The “big ideas” of economics applied to everyday topics.

The Rise and Fall of the Chinese Economy
OCT 20

Fair Trade: Does It Help Poor Workers?
JUL 08
International Finance

What causes international financial crises?

why is the forward premium puzzle, future spot rates are bette…
DEC 16

Request for citation: at the end of the video, Tyler says that e…
OCT 10
Development Economics

Why are some countries rich and others poor?

I think the benefits of hydro and dams is totally understated. …
DEC 28

. In your college town, real estate developers are building thou…
SEP 28
Great Economists: Classical Economics and its Forerunners

Why is Adam Smith the greatest economist of all time?

Interesting in what Smith describes of Malt taxes is similar of …
MAR 29

Adam Smith’s argument for a “strategic trade policy” contrasts w…
SEP 28
The Eurozone Crisis

What’s the future of the European Union and the Euro?

I understand about the different capital inflows and outflows bu…
MAR 23

Hi Tyler: 15 months after this speech, would you still stand by …
SEP 02
Economic History of the Soviet Union

Explore one of the greatest economic experiments of the twentieth century.

Can you provide an explanation of how the events listed in the v…
JUN 19

Hmm, I’m a bit uneasy about the interpretation of Marx and Lenin…
JUN 10
International Trade

Trade shapes the fortunes of nations. What are its effects?

Maybe in those cases the benefits of tariffs were not direct? On…
MAR 08

Is there a way to embed this video? I’d like to use it for my Gl…
DEC 30
Mexico’s Economy: Current Prospects and History

Is Mexico the most dynamic economy in Latin America?

I am watching videos on Mexicos very powerful and intimidating D…
MAY 25

Mexico and the 2008 Global Financial Crisis
MAY 02
Economics of the Media

The economics of the media and how government policy affects it.

I have a question related to your paper “An Economic Theory of A…
JAN 08

‘ You’re own natural views’ lol, i have no idea what that means?…
NOV 03

Introduction to Microeconomics
The Demand Curve
The Supply Curve
The Equilibrium Price
A Deeper Look at the Demand Curve
The Demand Curve Shifts
A Deeper Look at the Supply Curve
The Supply Curve Shifts
Exploring Equilibrium
Does the Equilibrium Model Work?
Supply and Demand Terminology
Elasticity of Demand
Calculating the Elasticity of Demand
Elasticity of Supply
Elasticity and Slave Redemption
Applications Using Elasticity
Commodity Taxes
Who Pays the Tax?
Tax Revenue and Deadweight Loss
Wage Subsidies
I, Rose
A Price Is a Signal Wrapped up in an Incentive
Markets Link the World
The Great Economic Problem
Information and Incentives
Prediction Markets
Price Ceilings
Price Ceilings: Shortages and Quality Reduction
Price Ceilings: Lines and Search Costs
Price Ceilings: Deadweight Loss
Price Ceilings: Misallocation of Resources
Price Ceilings: Rent Controls
Price Floors: The Minimum Wage
Price Floors: Airline Fares
Why Do Governments Enact Price Controls?
Price Controls and Communism
The Big Ideas of Trade
Comparative Advantage
Another Look at Comparative Advantage
Comparative Advantage Homework
Tariffs and Protectionism
Arguments Against International Trade
An Introduction to Externalities
External Benefits
Command and Control Solutions
The Coase Theorem
Trading Pollution
A Deeper Look at Tradeable Allowances
Introduction to the Competitive Firm
Maximizing Profit under Competition
Maximizing Profit and the Average Cost Curve
Entry, Exit, and Supply Curves: Increasing Costs
Entry, Exit, and Supply Curves: Constant Costs
Entry, Exit, and Supply Curves: Decreasing Costs
Minimization of Total Industry Costs of Production
The Balance of Industries and Creative Destruction
Maximizing Profit under Monopoly
The Monopoly Markup
The Costs and Benefits of Monopoly
Introduction to Price Discrimination
The Social Welfare of Price Discrimination
The Marginal Product of Labor
Human Capital and Signaling
The Tradeoff Between Fun and Wages
Compensating Differentials
Do Unions Raise Wages?
Public Goods and Asteroid Defense
A Deeper Look at Public Goods
Club Goods
The Tragedy of the Commons
Asymmetric Information and Used Cars
Asymmetric Information in Health Insurance
Moral Hazard
Solutions to Moral Hazard
Principles of Economics: Microeconomics How Much of Your Audience is Fake How Much of Your Audience is Fake

Marketers thought the Web would allow perfectly targeted ads.
Hasn’t worked out that way.

By Ben Elgin, Michael Riley, David Kocieniewski, and Joshua Brustein

Ron Amram has been in the brand marketing business for about 20 years. In the 2000s he was media director for Sprint’s prepaid cellular group, mainly figuring out where the carrier should spend its ad dollars—print, outdoor, digital, or broadcast. TV was always at the top of the pyramid. A TV campaign was like “the Air Force,” Amram says. “You wanted to get your message out, you did carpet bombing.” But TV wasn’t cheap, nor did it solve “that age-old question: Half of my marketing is working, half of it is not, and I don’t know which half.”

About 10 years ago, not long after Google went public and Yahoo! was still worth upward of $50 billion, attitudes shifted. Digital search and display ads had the potential to reach TV-size audiences at a fraction of the price. “People thought it was going to change everything,” Amram says.

The euphoria escalated again around 2010 with the arrival of programmatic advertising, a typically banal industry term for what is, essentially, automation. The ideal programmatic transaction works like this: A user clicks on a website and suddenly her Internet address and browsing history are packaged and whisked off to an auction site, where software, on behalf of advertisers, scrutinizes her profile (or an anonymized version of it) and determines whether to bid to place an ad next to that article. Ford Motor could pay to put its ads on websites for car buffs, or, with the help of cookies, track car buffs wherever they may be online. Ford might want to target males age 25-40 for pickup-truck ads, or, better yet, anybody in that age group who’s even read about pickups in the past six months.

That’s a stunningly attractive proposition to advertisers: surgical strikes on a carpet bombing scale. Ominous for privacy advocates, sure, but nirvana for agencies, publishers, and advertisers. At long last, they’d know where every last dollar went and whether it did its job.

Amram is at Heineken USA now, where the annual ad budget is in the $150 million range. In 2013 the company replaced its old stubby bottles with a fashionably long-necked version that supposedly keeps the beer cold longer. “We had a healthy investment in TV, local media, and digital,” he says. “We thought digital would come close and compete with television in terms of effectiveness.”

Late that year he and a half-dozen or so colleagues gathered in a New York conference room for a presentation on the performance of the online ads. They were stunned. Digital’s return on investment was around 2 to 1, a $2 increase in revenue for every $1 of ad spending, compared with at least 6 to 1 for TV. The most startling finding: Only 20 percent of the campaign’s “ad impressions”—ads that appear on a computer or smartphone screen—were even seen by actual people.

“The room basically stopped,” Amram recalls. The team was concerned about their jobs; someone asked, “Can they do that? Is it legal?” But mostly it was disbelief and outrage. “It was like we’d been throwing our money to the mob,” Amram says. “As an advertiser we were paying for eyeballs and thought that we were buying views. But in the digital world, you’re just paying for the ad to be served, and there’s no guarantee who will see it, or whether a human will see it at all.”

Increasingly, digital ad viewers aren’t human. A study done last year in conjunction with the Association of National Advertisers embedded billions of digital ads with code designed to determine who or what was seeing them. Eleven percent of display ads and almost a quarter of video ads were “viewed” by software, not people. According to the ANA study, which was conducted by the security firm White Ops and is titled The Bot Baseline: Fraud In Digital Advertising, fake traffic will cost advertisers $6.3 billion this year.

One ad tracked in the study was a video spot for Chrysler that ran last year on, a site based on the food and travel lifestyle magazine. Only 2 percent of the ad views registered as human, according to a person who was briefed on data provided to the study’s participants. Chrysler, which doesn‘t dispute the data, ceased buying ads on the site once it became aware of the “fraudulent activity,” says Eileen Wunderlich, the automaker’s spokeswoman. White Ops, which left out the names of the advertiser and website in its published study, declined to comment. Executives at Bonnier, the publishing company behind, say they screen every impression and that the White Ops study looked at 5,700 ads, a very small number. They also say there are multiple methods for detecting nonhuman traffic, and that there’s no single standard used by the industry. “We weren’t aware of any problem or complaint. If it had been brought to our attention we would have fixed it,“ says Perri Dorset, a Bonnier spokeswoman.

Fake traffic has become a commodity. There’s malware for generating it and brokers who sell it. Some companies pay for it intentionally, some accidentally, and some prefer not to ask where their traffic comes from. It’s given rise to an industry of countermeasures, which inspire counter-countermeasures. “It’s like a game of whack-a-mole,” says Fernando Arriola, vice president for media and integration at ConAgra Foods. Consumers, meanwhile, to the extent they pay attention to targeted ads at all, hate them: The top paid iPhone app on Apple’s App Store is an ad blocker.

“I can think of nothing that has done more harm to the Internet than ad tech,” says Bob Hoffman, a veteran ad executive, industry critic, and author of the blog the Ad Contrarian. “It interferes with everything we try to do on the Web. It has cheapened and debased advertising and spawned criminal empires.” Most ridiculous of all, he adds, is that advertisers are further away than ever from solving the old which-part-of-my-budget-is-working problem. “Nobody knows the exact number,” Hoffman says, “but probably about 50 percent of what you’re spending online is being stolen from you.”

Bonnier is a 211-year-old Swedish media conglomerate. Like a lot of traditional publishing companies, it has struggled in its transition to the Internet era. Generating digital revenue to offset declines in the print business is paramount, and video ads are particularly lucrative. Last year the company began to build videocentric sites for Saveur and several of its other titles, including Outdoor Life, Working Mother, and Popular Science.

About half of’s home page is taken up by a player that automatically plays videos with simple kitchen tips. In early September, the spots (How to Stir a Cocktail, Step One: “Hold the spoon between pointer and middle finger …”), were preceded by ads from Snapple and Mrs. Meyer’s household cleaning products.

The challenge for Bonnier was building an audience. That can be done organically—by coming up with lots of content, promoting it until people start watching, persuading advertisers to buy in. Or there’s a modern shortcut: Buy traffic. Which doesn’t necessarily mean fake it. Publishers often pay to redirect human users from somewhere else on the Internet to their own sites, and companies such as Taboola and Outbrain specialize in managing this kind of traffic. Website A hires Taboola, which pays Website B to put “content from around the Web” boxes at the bottom of its pages. Viewers, enticed by headlines like “37 Things You Didn’t Know About Scarlett Johansson,” click on a box and are redirected to Website A. But redirects are also expensive. In practice, only 2 percent of people on a site click on these boxes, and Website A has to compensate Website B handsomely for giving up precious visitors.

Less ethical methods are cheaper. Pop-ups—those tiny browser windows that you ignore, click to close, or never see—are one way to inflate visitor numbers. As soon as that window appears on your computer, you’re counted as someone who’s seen the ads. An even more cost-effective technique—and as a rule of thumb, fake is always cheaper—is an ad bot, malware that surreptitiously takes over someone else’s computer and creates a virtual browser. This virtual browser, invisible to the computer’s owner, visits websites, scrolls through pages, and clicks links. No one is viewing the pages, of course; it’s just the malware. But unless the bot is detected, it’s counted as a view by traffic-measuring services. A botnet, with thousands of hijacked computers working in concert, can create a massive “audience” very quickly.

All a budding media mogul—whether a website operator or a traffic supplier—has to do to make money is arbitrage: Buy low, sell high. The art is making the fake traffic look real, often by sprucing up websites with just enough content to make them appear authentic. Programmatic ad-buying systems don’t necessarily differentiate between real users and bots, or between websites with fresh, original work, and Potemkin sites camouflaged with stock photos and cut-and-paste articles.

Bonnier wasn’t that audacious. But even its own executives say the content on the video sites was unlikely to create and sustain much of an audience on its own. So they turned to several different traffic brokers—or audience networks, to use the industry euphemism. Sean Holzman, Bonnier’s chief digital revenue officer, described the practice as normal for big-time publishers, especially those rolling out new products, because advertisers won’t bother with sites that don’t already have an audience. “It was a test, a way to prime the pump and see if we could build these sites at this price point,” he says. “You usually have to keep buying some traffic, because the audience you’re getting isn’t as sticky.” Carbon-Rahmen und Android-Konsole Carbon-Rahmen und Android-Konsole

Smartphone- und Fahrradtechnik verbünden sich und heraus kommt ein Smart Bike. Das Fahrrad Le Syvrac vom chinesischen Hersteller Le Eco beherrscht fast alles, was ein Smartphone kann – und noch mehr.

UMTS-Unterstützung, WLAN, Bluetooth und GPS-Empfänger: klingt wie ein Smartphone, ist aber ein Fahrrad. Der chinesische Hersteller Le Eco hat auf dem Mobile World Congress 2016 in Barcelona Handelspartnern und Journalisten sein Modell Le Syvrac mit Android-Konsole gezeigt. Es ähnelt von der technischen Ausstattung her einem Smartphone.

Das Smart Bike hat eine zentrale Steuerungseinheit, die so ins Chassis eingebaut wurde, dass sie mittig im Lenker untergebracht ist. Damit kann der Radfahrer gut auf den 4 Zoll großen Touchscreen schauen. Auf dem Gerät läuft eine von Le Eco angepasste Android-Version, die der Hersteller als Bike OS bezeichnet.

Der Startbildschirm ist ein digitaler Tacho, der die Geschwindigkeit, die zurückgelegte Strecke und ähnliche Informationen anzeigt. Aus dem Startbildschirm heraus sind die wichtigsten Funktionen direkt erreichbar, so etwa die Routenplanung, der Musikplayer oder die Statistik-App.

Darüber hinaus kann sich der Fahrer vom Rad einen Tourenvorschlag anbieten lassen, wenn das Ziel ist, einfach eine bestimmte Zeit oder Strecke zu fahren und dann wieder am Ausgangspunkt anzukommen. Das Bike OS wird über recht große Symbole gesteuert, um Fehlbedienungen zu verhindern. In den Einstellungen sind dann aber recht kleine Elemente vorhanden. Damit wird die Android-Konsole für Aufgaben verwendet, die sonst von Smartphones erledigt werden.

Die Android-Konsole beherbergt auch Lautsprecher, um bei der Fahrt Musik hören zu können. Alternativ dazu kann der Musik auch über ein Bluetooth-Headset gelauscht werden. Die eingebauten Lautsprecher machten beim Ausprobieren ordentlich Krach, neigten aber bei maximaler Lautstärke zu Verzerrungen. Die Lautstärke kann über passende Knöpfe am Lenker leiser und lauter gestellt werden.

Im Lenker befinden sich weitere Besonderheiten: So ist auf jeder Seite ein Blinker untergebracht, um einen Abbiegevorgang anzuzeigen. Außerdem befinden sich in den Lenkergriffen Pulssensoren, mit denen der Puls gemessen und zur Auswertung an die Android-Konsole übermittelt wird. Intels Android-Smartphone mit integriertem Desktop-Linux Intels Android-Smartphone mit integriertem Desktop-Linux

Zusammen mit Foxconn zeigt Intel ein produktionsreifes Android-Smartphone, das auf einem angeschlossenen Monitor parallel Debian Linux anzeigen kann. Grundlage ist Intels Atom-X3-Prozessor, der Kostenfaktor des Gerätes liegt bei unter 100 US-Dollar.

Auf dem Mobile World Congress (MWC) 2016 hat Intel ein zusammen mit Foxconn entwickeltes Smartphone gezeigt, das neben Android parallel auch Debian Linux installiert hat. Das Linux-System wird per HDMI-Adapter auf einem Fernseher oder Monitor angezeigt, gleichzeitig bleibt das Android-System weiter nutzbar.

Das Foxconn-Smartphone steht stellvertretend für eine ganze Reihe preiswerter Smartphones, die über den zusätzliche Debian-Desktop verfügen. Zielmarkt sind Schwellenländer, in denen ein Großteil der Nutzer mit einem Smartphone ins Internet gehen und die Verbreitung von PCs niedrig ist. Das günstige Smartphone soll den Zugang zu PC-Funktionen wie Textverarbeitung ermöglichen.

Grundlage der Geräte ist Intels Atom-X3-Prozessor (Sofia) – welche Variante in dem uns gezeigten Gerät verbaut wurde, ist unklar. Die Android-Debian-Kombination wurde ebenfalls von Intel entwickelt. Nachdem das Smartphone über einen USB-HDMI-Adapter an einen Monitor angeschlossen wurde, wird der Debian-Modus über eine Schaltfläche aktiviert. Anschließend wird das Smartphone-Display ausgeschaltet, und der Desktop-Modus auf dem Monitor aktiviert. Beide Displays gleichzeitig lassen sich aktuell noch nicht nutzen.

Allerdings kann der Nutzer über die Debian-Oberfläche jederzeit den Startbildschirm des Android-Systems seines Smartphones aufrufen und bedienen. Die Funktionen bleiben die ganze Zeit über erhalten – Nachrichten lassen sich über das eingeblendete Android ebenso aufrufen und beantworten wie Anrufe tätigen. Das ist praktisch, um etwa während des Arbeitens weiterhin erreichbar zu sein.

Verbindet der Nutzer eine Maus und eine Tastatur per Bluetooth mit dem Smartphone, lässt sich das Linux-System tatsächlich wie ein normales Debian auf einem PC verwenden. Allerdings wirkt es bereits auf den ersten Blick etwas abgespeckt – was es auch ist, wie uns der Chef des Entwicklerteams Nir Metzer erklärt.

“Wir haben alles Unwichtige gestrichen, um das System der Leistungsfähigkeit des Chips anzupassen”, sagt Metzer. Dabei sind wichtige Grundfunktionen wie der einfache Zugang zu Anwendungen beibehalten worden: Nutzer des Foxconn-Smartphones können sich – soweit die Rechenleistung des SoC mitspielt – alle Anwendungen installieren, die auch auf einem normalen PC mit Debian Linux installierbar sind.

Nutzer merken hauptsächlich an der grafischen Wiedergabe, dass das System entschlackt wurde. Der Hintergrund ist einfarbig, auf Übergangseffekte beim Öffnen und Schließen der Fenster wird auch verzichtet. Dafür können Nutzer in verschiedenen Fenstern unterschiedliche Anwendungen laufen lassen, wie uns Intel gezeigt hat. Während ein Video abgespielt wurde, liefen parallel verschiedene andere Programme sowie die Android-Übersicht.

Auf die auf dem Smartphone gespeicherten Daten haben sowohl Android als auch Debian Zugriff – getrennte Partitionen gibt es nicht, auch der Kernel wird von beiden Systemen verwendet. Auch Anwendungen stimmen sich mitunter untereinander ab: “Der E-Mail-Client von Debian synchronisiert sich zum Beispiel mit dem von Android”, erklärt Metzer.

Das System ist insgesamt überraschend gut nutzbar, auch wenn etwa beim Öffnen des Browsers kleine Wartezeiten eingeplant werden müssen. Texte mit Libre Office lassen sich ebenso gut schreiben wie Videos anschauen. Bequemer als auf einem Smartphone ist das allemal und stellt alles in allem doch einen guten Ersatz für einen merklich teureren PC dar.

Insbesondere die parallele Nutzung von Android und Debian hat uns gut gefallen. Bei einem Preis von unter 100 US-Dollar bekommen Käufer tatsächlich einen brauchbaren PC-Ersatz – mit all den Schwächen, die etwa die 2 GByte RAM und 16 GByte Flash-Speicher mit sich bringen.

Nir Metzer zufolge wird das Foxconn-Gerät so, wie wir es gezeigt bekommen haben, auf den Markt kommen – wann und wo konnte er uns nicht verraten. Die Technik, um derartig dual ausgestattete Smartphones zu produzieren, besteht dank der Atom-X3-Serie bereits länger. Allerdings müssten sich Hersteller die Mühe machen, die Software auf die Hardware zuzuschneiden. Das hat Intel getan – mit einem überraschend guten Ergebnis.



My name is Tom. Eight years ago I created the fun programming game AntMe! to act on my conviction that the shortage of skilled workers in our IT industry was related to the inadequate and outdated learning materials used by our education system.

Students need to experience flashes of successes—it’s those moments of revelation when you see a concept in action and understand: I did that, and I know how I did it, that make learning fun and lead to enduring interest in the subject. And that’s exactly what makes AntMe! so successful. Students quickly begin writing their first lines of code and bringing the ants to life. It’s fun, it’s exciting, and it brings boys and, crucially, girls as well closer to IT in a playful way.

My goal is to offer the game for free to schools and universities—but to do that, I need your support. If you’re a company that depends on well-trained IT experts, or if you train them yourself, then let’s discuss a sponsoring or investment package. I appreciate every kind of support.



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