Econ 101: Discriminación de precios: Primero, segundo y tercer grado

Discriminación de precios 

La discriminación de precios es la práctica de cobrar un precio diferente por el mismo bien o servicio. Hay tres tipos de discriminación de precios - en primer grado, segundo grado, y la discriminación de precios de tercer grado.

Primer grado
La discriminación de primer grado, alternativamente conocida como la discriminación de precios perfecta, se produce cuando una empresa cobra un precio diferente para cada unidad consumida.
La empresa es capaz de cobrar el precio máximo posible para cada unidad que permite a la empresa capturar todos los excedentes del consumidor disponibles por sí mismo. En la práctica, la discriminación de primer grado es rara.

Segundo grado
La discriminación de precios de segundo grado significa cobrar un precio diferente para diferentes cantidades, tales como descuentos por volumen para compras al por mayor.

Tercer grado
La discriminación de precios de tercer grado significa cobrar un precio diferente a los distintos grupos de consumidores. Por ejemplo, los viajeros de tren y metro se pueden subdividir en cercanías y viajeros ocasionales y cinéfilos pueden subdividir en adultos y niños. La división del mercado en pico y pico de uso off es muy común y ocurre con el gas, la electricidad y el abastecimiento de teléfono, así como la membresía de un gimnasio y de las tarifas de aparcamiento. Discriminación de tercer grado es el tipo más común.

Condiciones necesarias para la discriminación éxito
La discriminación de precios sólo puede ocurrir si se cumplen ciertas condiciones.

1. La empresa debe ser capaz de identificar los diferentes segmentos de mercado, como los usuarios domésticos y los usuarios industriales.
2. Diferentes segmentos deben tener diferentes elasticidades precio (PED).
3. Los mercados deben mantenerse separados, ya sea por el tiempo, la distancia física y la naturaleza de su uso, tales como edición de 'Escuelas' Microsoft Office, que solo está disponible para las instituciones educativas, a un precio inferior.
4. No tiene que haber infiltraciones entre los dos mercados, lo que significa que un consumidor no puede comprar al precio bajo en el submercado elástica, y luego revender a otros consumidores en el sub-mercado inelástico, a un precio mayor.
5. La empresa debe tener un cierto grado de poder de monopolio.

Video

Diagrama de discriminación de precios
Si suponemos que el coste marginal (MC) es constante en todos los mercados, si el mercado se divide, se igualará el costo total medio (ATC). La maximización del beneficio se producirá en el precio y de salida en MC = MR. Si el mercado puede ser separado, el precio y la producción en el submercado inelástica será P y Q y P1 y Q1 en el submercado elástica.

Cuando se separan los mercados, los beneficios serán la zona MC, P,X,Y + MC1,P1,X1,Y1. Si el mercado no puede ser separado, y los dos submercados se combinan, los beneficios serán la zona MC2,P2,X2,Y2.

Si los beneficios de separar los sub-mercados es mayor que para la combinación de los sub-mercados, entonces el beneficio racional maximizar monopolista discrimina precio.

Separación de mercados y elasticidad
La discriminación es sólo un valor de empresa, si el beneficio de separación de los mercados es mayor que de mantener los mercados combinados, y esto dependerá de las elasticidades de la demanda en los sub-mercados. Los consumidores en el submercado inelástica deberán pagar el precio más alto, y los que en el submercado elástica se cobrará el precio más bajo.

Economics Online

La composición del gasto en los hogares estadounidenses

Where Americans—Rich and Poor—Spent Every Dollar in 2012

Food, clothes, and housing account for more than 60 percent of all spending among the poor.

DEREK THOMPSON - The Atlantic

Here it is, fresh from the Bureau of Labor Statistics: all of American spending in one big color wheel.

Since some of you (inexplicably) don't like pie charts, here's the same data in bars.

Averages are misleading, particularly when the rich are running away from the rest. So, digging deeper into BLS data, I broke out percent spending by category for the richest and poorest 20 percent.

For the poor, food, clothes, and housing account for more than 60 percent of all spending. The rich have more left over for leisure, insurance, and savings.

The term consumption takes on a more literal meaning when you see the difference between rich and poor spending. Cash-hungry families consume more of their income immediately, spending two in three dollars on absolute essentials like food and shirts. The rich are more predisposed to spend toward the future, with eight-times more of their income going toward insurance and even more going toward savings (although the bottom 20 percent includes lots of retirees on Social Security, the next quintile doesn't see much in the way of savings either).

There has been a good amount of research recently about how being poor changes your thinking about everything. "If you have very little, you often behave in such a way so that you'll have little in the future," Sendhil Mullainathan recently told Harold Pollack in Wonkblog. The poor don't plan as much for the coming years, because they can't afford to. 

Thinking about the future is a form of luxury.

Update: First graph edited to reflect housing's true share of spending.

Krugman: Burbujas, regulación y estancamiento secular

Bubbles, Regulation, and Secular Stagnation

Looking at current macroeconomic policy, the obvious question is, stupid or evil? And the obvious answer is, why do we have to choose?

But it is, I think worthwhile – or at any rate soothing – to think about the longer-term future for monetary and fiscal policy. I recently talked about some of these issues with Adair Turner, and I thought I might write up my version of the story so far (just to be clear, Adair bears no responsibility for any errors or confusion in what follows). In brief, there is a case for believing that the problem of maintaining adequate aggregate demand is going to be very persistent – that we may face something like the “secular stagnation” many economists feared after World War II.

So, let’s start with the basic role of monetary policy in stabilizing the economy. Many, probably most macroeconomists – or at any rate those who think at all about policy – think of that role something like this:

Figure 1: Normal monetary policy

Here IS shows how overall real spending and hence the level of real GDP depends on the real interest rate. We think of the central bank as being able to set the real interest rate; its goal is to set that rate at a level that keeps the economy near potential output, which in turn is consistent with low and stable inflation. This is equivalent conceptually to setting the rate at the Wicksellian natural interest rate.

Not that long ago, macroeconomists were congratulating central bankers (and central bankers were, of course, congratulating themselves) over doing a pretty good job of getting this right. Inflation, occasional commodity shocks aside, was indeed low and stable, and from 1985 to 2007 the real economy was fairly stable too.

Figure 2: Inflation was good …

Then came catastrophe – and as so often happens, when the house collapses you find the skeletons that were lurking in the closet all along. The stability of prices and output masked an underlying unsustainable growth in leverage:

Figure 3: … but trouble was brewing. Household liabilities as percent of GDP.

It was a Minsky moment waiting to happen, and happen it did.

When the Minsky moment came, there was a rush to deleverage; this drove down overall demand for any given interest rate, and made the Wicksellian natural rate substantially negative, pushing us into a liquidity trap:

Figure 4: The liquidity trap.

This meant that monetary policy could no longer do the job of stabilizing the economy: Central banks found themselves up against the zero lower bound. Fiscal policy could and should have helped, and automatic stabilizers did help mitigate the slump. But fiscal discourse went completely off the rails, and overall we had unprecedented austerity when we should have had stimulus.

So we’ve had an economic disaster – and our inability to avoid this disaster makes a mockery of all the self-congratulation of the years that preceded it.

But how should pre-2008 policy have been different? And what should policy look like looking forward?

There are many economic commentators who take rising leverage, asset bubbles and all that as prima facie evidence that monetary policy was too loose; some argue that the Fed kept rates too low for too long after the 2001 recession, some argue that interest rates were too low over the whole period from 1985 to 2007.

The trouble with this line of argument is that if monetary policy is assigned the task of discouraging people from excessive borrowing, it can’t pursue full employment and price stability, which are also worthy goals (as well as being the Fed’s legally binding mandate). Specifically, since the US economy shows no signs of having been overheated on average from 1985 to 2007, the argument that the Fed should nonetheless have set higher rates is an argument that the Fed should have kept the real economy persistently depressed, and unemployment persistently high – and also run the risk of deflation – in order to keep borrowers and lenders from making bad decisions. That’s quite a demand.

Many of us would therefore argue that the right answer isn’t tighter money but tighter regulation: higher capital ratios for banks, limits on risky lending, but also perhaps limits for borrowers too, such as maximum loan-to-value ratios on housing and restrictions on second mortgages. This would guard against bubbles and excessive leverage, while leaving monetary policy free to pursue conventional goals.

Or would it?

Our current episode of deleveraging will eventually end, which will shift the IS curve back to the right. But if we have effective financial regulation, as we should, it won’t shift all the way back to where it was before the crisis. Or to put it in plainer English, during the good old days demand was supported by an ever-growing burden of private debt, which we neither can nor should expect to resume; as a result, demand is going to be lower even once the crisis fades.

And here’s the worrisome thing: what if it turns out that we need ever-growing debt to stay out of a liquidity trap? What if the economy looks like Figure 4 even after deleveraging is over? Then what?

This is not a new fear: worries about secular stagnation, about a persistent shortfall of demand even at low interest rates, were very widespread just after World War II. At the time, those fears proved unfounded. But they weren’t irrational, and second time could be the charm.

Bear in mind that interest rates were actually pretty low even during the era of rising leverage, and got worryingly close to zero after the 2001 recession and even, you might say, after the 90-91 recession (there was talk of a liquidity trap even then). It’s not hard to believe that liquidity traps could become common, if not the norm, in an economy in which prudential action, public and private, has brought the era of rising leverage to an end.

And in that case, then what?

We might try to figure out why we seem to need leverage and bubbles to have full employment, and try to fix it. More thoughts on that on another day. But what if that isn’t an option?

One answer could be a higher inflation target, so that the real interest rate can go more negative. I’m for it! But you do have to wonder how effective that low real interest rate can be if we’re simultaneously limiting leverage.

Another answer could be sustained, deficit-financed fiscal stimulus. But, you say, this would lead to exploding public debt! Actually, no – not if the real interest rate is persistently below the economy’s growth rate, which it will certainly be if it’s persistently negative. In that case the government can run a primary deficit even while keeping the debt-GDP ratio constant – and the higher the level of debt, the higher the allowable deficit.

OK, I’m shooting from the hip here. The main point is simply that the weirdness of our current situation may well go on much longer than anyone currently imagines.

NYT

Trabajadores excesivamente educados en USA

1 de cada 5 trabajadores estadounidenses: Estoy demasiado educado para mi trabajo
En realidad, eso no es tan malo, según los estándares internacionales.

Reuters
Cuando los estadounidenses no están preocupados sobre el ser sin educación, estamos por lo general preocupándose por sobreeducación.

Cada cierto tiempo, los escritores y académicos empiezan sonar la alarma sobre un exceso procedente de los graduados universitarios que terminan condenados a una vida de subempleo. Y, cuando la economía baja, esas advertencias pueden parecer bastante razonable.

Es por eso que la tabla de abajo, de un reciente informe de la OCDE sobre las habilidades empleos en todo el mundo, me llamó la atención. A pesar de que no se ocupa específicamente de la educación universitaria, muestra que alrededor del 19 por ciento de los estadounidenses dicen que tienen más educación que sea necesario para tener derecho a su trabajo. Eso es en realidad inferior a la media entre los 22 países mencionados. En Japón y en el Reino Unido, la cifra es de alrededor de 30 por ciento. En el otro extremo del espectro en Italia, que es alrededor del 13 por ciento.



Así que en realidad hay un montón de sobre-educados estadounidenses - y en inglés y japonés, y los australianos y estonios para el caso, también. Curiosamente, el informe de la OCDE constata que, según los puntajes de alfabetización, la mayoría de los trabajadores que dicen estar sobrecualificados para su empleo son probablemente muy adecuadas para ellos en términos de sus habilidades primas. Por lo tanto, podría ser que en un país con un sistema educativo que funcione, las credenciales de algunas personas van a superar a sus talentos.

The Atlantic

Las sociedades sin efectivo

We are so far away from the cashless society, reveals new study from Mastercard
By Christopher Mims @mims

Consumers in rich countries don’t buy expensive things with cash, reveals ground-breaking new study.Mastercard

How far are we from the mythical “cashless society”? A new study from Mastercardseems to suggest that, as measured by the dollar amount of consumer transactions, some countries are but a hairsbreadth away already, with only 7% of the value of consumer transactions taking place in cash in Belgium, 8% in France and 10% in Canada.
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But there’s a great big asterisk to all of this: Consumer purchases constitute only 11% of all payments worldwide, or $2.8 trillion of $592 trillion, once you throw in what governments and business spend.
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Consumers just don’t spend that much, compared to businesses and governments.Mastercard

Cashless transactions aren’t beating cash transactions if you count up the number of transactions, rather than their value. In fact, 85% of all transactions are conducted in cash. But the much higher average value of non-cash transactions means that only 34% of the value of all consumer transactions worldwide was in cash.
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Cash is really popular—but not for big-ticket items.

China, for example, saw a 20% drop in the value of cash payments for consumer goods between 2006 and 2011, and now 55% of the value of transactions in the country were non-cash.
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Cash also still has uses beyond small, everyday transactions; black markets, criminal syndicates and tax evasion all require it. It’s just that, especially in rich countries, it’s easier to use something like, oh, a Mastercard. The ongoing utility of cash is one reason that the US $100 bill is more popular than ever—mostly as ameans of exchange outside the US.

Quartz

Los mejores estudiantes están mejor en las peores escuelas

High-achieving students are better off in worse schools

By Josephine Lethbridge
Josephine Lethbridge is an assistant editor at The Conversation.

Muddling in the middle. Reuters/Luke MacGregor

There is an assumption that children perform better among highly achieving peers. High class achievement might be thought to indicate better teaching, or to induce academic competition between students. However, new research counters (pdf) this common assumption.

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Felix Weinhardt and Richard Murphy, from the Center for Economic Performance at the London School of Economics, analyzed administrative data of over 2.3 million British schoolchildren. This data was used to assess how primary school rank affected later exam results. Pupils were compared on leaving primary school at KS2 (age 11) and at secondary school KS3 (age 14).

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Imagine two primary school pupils of a the same ability. One is at the top of a class, whereas the other is in the middle, at a better performing school. The results find that the first student performs better at secondary school, implying the significance of rank—and confidence.

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The scale of the effect is large if you look at it in the context of recent education studies. The teacher effect literature (pdf), for example, says a teacher who is one standard deviation better than the average can improve test scores by one point on a one to 100 scale. “We find that moving up one standard deviation in rank similarly improves test scores,” said Weinhardt. “That’s why we say the rank effect is comparable to being taught by a good teacher.”

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Another way to think about the scale of the effect, Weinhardt explained, is that “moving up half the rank distribution in primary school—from the middle to the top of the class—is equivalent to about three extra month of schooling (pdf).”

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In boys, this effect is significantly more pronounced. The study indicates that boys gain four times more in later test scores from being top of the class, compared to girls. Boys were also more affected by being ranked below the median level. Being ranked below average tended to cause boys to underachieve at KS3.

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Tina Rampino, a research student at the University of Essex, commented on why this gender difference is so pronounced. “Boys and girls are brought up to socialize differently,” she said. “Girls tend to be taught to behave, and they tend to be under stricter parental supervision. Therefore, they tend to do better in school. Boys, on the other hand, are brought up to be more competitive than girls.”

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Sending your children to the “best” school, particularly in the case of boys, is therefore perhaps not the best idea.

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The research is mostly relevant on an individual level. “Of course, whatever way you organize classes,” Weinhardt said, “half the students are going to lose out. It is the local comparisons that matter. What our research reveals is the importance of motivational confidence issues in education.”

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“Drawing attention to rank is highly beneficial in the case of some children and in others, not. Sometimes you should compare students, and sometimes you shouldn’t. Parents and teachers should be more aware of this, and consider different ways of building up confidence.”

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This post originally appeared at The Conversation.

Quartz

Shiller muestra dos gráficos importantes de los últimos 20 años

Nobel Prize Winner Robert Shiller Is Responsible For The 2 Most Important Charts Of The Last Two Decades

SAM RO

Yale University professor Robert Shiller was one of three people to win the 2013 Sveriges Riksbank Prize in Economic Sciences (also known as the Nobel Prize in Economics).

Shiller is already a god among economists. He famously predicted two of the biggest bubbles of all time: the dot-com bubble and the housing bubble.  Both times, he published an edition of his book Irrational Exuberance, which described and predicted each respective bubble.

The theme of this year's award "Trendspotting in asset markets," and the Nobel committee pointed to Shiller's work in forecasting intermediate-term moves in asset prices.

"He found that stock prices fluctuate much more than corporate dividends, and that the ratio of prices to dividends tends to fall when it is high, and to increase when it is low," said the Nobel Committee. "This pattern holds not only for stocks, but also for bonds and other assets."

Shiller regularly updates his data and makes it available for free online.

He is responsible for two charts, that everyone in finance follow very closely.

The first chart is of the cyclically-adjusted price-earnings (CAPE) ratio.  CAPE is calculated by taking the S&P 500 and dividing it by the average of ten years worth of earnings.  If the ratio is above the long-term average of around 16, the stock market is considered expensive. Shiller has argued that the CAPE is remarkably good at predicting returns over the period of several years.

As you can see, the CAPE ratio reached insanely high levels during the dotcom bubble.

Yale

The second chart is of a long-term look at home prices adjusted for inflation.

During the early 2000s, home prices took off, forcing Shiller to publish the second edition of Irrational Exuberance.

As you can see, homes are not great assets if you're looking for real returns.

"Housing traditionally is not viewed as a great investment," he told Bloomberg's Trish Regan earlier this year. "It takes maintenance, it depreciates, it goes out of style. All of those are problems. And there's technical progress in housing. So, new ones are better.

"So, why was it considered an investment? That was a fad. That was an idea that took hold in the early 2000's. And I don't expect it to come back. Not with the same force. So people might just decide, "Yeah, I'll diversify my portfolio. I'll live in a rental." That is a very sensible thing for many people to do."

Yale

No one will argue that Shiller wasn't deserving of the Nobel prize. If anything, it was long overdue.

Business Insider

17 imágenes de la globlalización

The Global Economy In 17 Beautiful Maps
WALTER HICKEY

Walter Hickey/ BI, data via Countrylicious

El ecosistema de la economía mundial es una máquina compleja con miles de piezas móviles.

Por suerte, encontramos Countrylicious, un proyecto excepcional por el ingeniero de software rumano Daniel Chirita.

El sitio cuenta con grandes cantidades de datos recogidos de fuentes abiertas en torno a la economía de nuestro planeta, y Chirita fue lo suficientemente amable para hacernos publicamos algunos. En el caso de que los datos no fueron ya realizadas en un mapa con sombra, tomamos su información mad hizo uno.

Echa un vistazo a lo que hace que la garrapata economía global.

Countrylicious

But when you divide GDP by population, y ou can see individual national productivity come forward, who is punching above their weight.


Countrylicious

Take a look at the explosive growth in emerging markets. Post-Gaddafi Libya is just exploding.


Countrylicious

Also worth taking a look at is the industrial production growth rate. Tiny Qatar is the winner here.


Walter Hickey/ BI, data via Countrylicious

Inflation Hawks, take note. The U.S. is doing pretty good here.


Countrylicious

This map shows world unemployment. Even leaving a recession the U.S. is looking pretty.


Countrylicious

Youth Unemployment is a major international issue that is only starting to be addressed.


Countrylicious

The percent the state taxes across the globe varies wildly by nation.


Walter Hickey/ BI, data via Countrylicious

Here's who is selling to the world.


Walter Hickey/ BI, data via Countrylicious

And here's who's buying.


Walter Hickey/ BI, data via Countrylicious

The international energy market is another fascinating story.


Walter Hickey/ BI, data via Countrylicious

Here's who is selling.


Walter Hickey/ BI, data via Countrylicious

Here's who is buying.


Walter Hickey/ BI, data via Countrylicious

Another awesome look at the global economy is the mobile penetration in each nation.


Walter Hickey/ BI, data via Countrylicious

Even moreso is the Internet penetration. There's a whole world out there without the web.


Walter Hickey/ BI, data via Countrylicious

Here's how much each nation is investing in their children.


Countrylicious

And, in a map that is by and large the converse of the previous map, the ones buying a military.

Business Insider

Argentina... "entorno inviable para negocios"

Grupo Elektra abandona Argentina por entorno inviable para negocios

La compañía mexicana, propiedad de Ricardo Salinas, explicó en un comunicado enviado a la Bolsa Mexicana de Valores que esta "decisión resulta de un difícil entorno macroeconómico y de negocios, que resta viabilidad a la operación en ese país".

También denunció que en ese país (Argentina) "existe una cultura de no pago de adeudos que hace inviable el negocio del crédito".

El mexicano Grupo Elektra, que opera más de 6.500 puntos de venta en México y otros países, anunció el retiro de sus inversiones y operaciones en Argentina, entre otros factores por el control cambiario y las restricciones al comercio exterior.

La compañía, propiedad de Ricardo Salinas, explicó en un comunicado enviado a la Bolsa Mexicana de Valores que esta "decisión resulta de un difícil entorno macroeconómico y de negocios, que resta viabilidad a la operación en ese país".


Explicó que entre los factores que hacen inviables los negocios está el "control cambiario y restricciones a importar y exportar que limitan el acceso a mercancías para el comercio, mientras que los controles al flujo de capitales restringen la inversión".

Además, señaló que la "alta inflación, dificulta la planeación de los negocios, mientras que la regulación laboral permite prácticas sindicales que afectan el ambiente de inversión".

También denunció que en ese país "existe una cultura de no pago de adeudos que hace inviable el negocio del crédito".

Elektra afirmó que sus operaciones en Argentina son "poco significativas" respecto al tamaño de la compañía, y aclaró que no mantiene actividades bancarias, las cuales han permitido desarrollar operaciones exitosas en otras regiones.

Con su salida de Argentina, Elektra, que además tiene presencia en Estados Unidos, Guatemala, Honduras, Perú, Panamá, El Salvador y Brasil, buscará concentrarse en otros mercados con mayores perspectivas de rentabilidad en beneficio de sus inversores.

Elektra forma parte del consorcio Grupo Salinas, que opera Televisión Azteca, una compañía de telefonía móvil y el Banco Azteca entre otras empresas.

América Economía

Keynes Was Right!?

Keynes tenía razón : la austeridad del Gobierno en tiempos de problemas es una mala idea

Estoy seguro que muchos de ustedes han visto el reciente estudio realizado por Thomas Herndon, un estudiante de economía graduado de 28 años de edad en la Universidad de Massachusetts Amherst. Si no es así, que se titula Does High Public Debt Consistently Stifle Economic Growth? A Critique of Reinhart and Rogoff [¿Una elevada deuda pública es consistente para ahogar el crecimiento económico? Crítica de Reinhart y Rogoff."] (Al citar se puede leer el artículo, descargar los datos, véanse las respuestas a la misma, etc.)

Para una buena visión general rápida, haga clic aquí.

He aquí un resumen aún más breve :

El artículo es una crítica devastadora del enfoque de austeridad recientemente defendida en los estados y otros países, que cínicamente pretende cortar y recortar el gobierno federal y estatal en la sumisión fiscal, mientras que las grandes empresas continúa su gran crecimiento en los mercados globales altamente dinámicos, ganar más dinero que nunca antes.



Lo que hace tan devastadora es que Henderson usa Reinhart y los propios datos de Rogoff : parece que los autores iniciales hechas a,, error de base de datos flagrante importante importante, olvidándose de codificar adecuadamente la información correcta, los autores iniciales también dejaron a tres de los países (Canadá, Nueva Zelanda y Australia), donde un enfoque caritativo y relajado para pasar resultó en un éxito significativo.

Lo que también hace el interesante trabajo desde una perspectiva de ciencias de la complejidad es el tema de la curva de montaje y el enfoque de Herndon de no linealidad en comparación con el enfoque adoptado por los autores iniciales.

(La figura de arriba fue tomada del trabajo de Herndon.)

De todos modos, creo que es un muy buen papel para leer, y, para aquellos de nosotros que enseñan las estadísticas y método, es un recordatorio malvados para compartir con nuestros estudiantes : siempre, siempre, siempre, verifique sus datos, y luego comprobar su los datos de nuevo! ! ! De todas las cosas que mi mentor, Galen Buckwalter me enseñó, que es una de esas cosas quemadas en la parte trasera de mi cerebro.

Sociology and Complexity Blog