19 ноября, 15:03

When Should You Adjust Standard Errors for Clustering? -- by Alberto Abadie, Susan Athey, Guido W. Imbens, Jeffrey Wooldridge

In empirical work in economics it is common to report standard errors that account for clustering of units. Typically, the motivation given for the clustering adjustments is that unobserved components in outcomes for units within clusters are correlated. However, because correlation may occur across more than one dimension, this motivation makes it difficult to justify why researchers use clustering in some dimensions, such as geographic, but not others, such as age cohorts or gender. This motivation also makes it difficult to explain why one should not cluster with data from a randomized experiment. In this paper, we argue that clustering is in essence a design problem, either a sampling design or an experimental design issue. It is a sampling design issue if sampling follows a two stage process where in the first stage, a subset of clusters were sampled randomly from a population of clusters, and in the second stage, units were sampled randomly from the sampled clusters. In this case the clustering adjustment is justified by the fact that there are clusters in the population that we do not see in the sample. Clustering is an experimental design issue if the assignment is correlated within the clusters. We take the view that this second perspective best fits the typical setting in economics where clustering adjustments are used. This perspective allows us to shed new light on three questions: (i) when should one adjust the standard errors for clustering, (ii) when is the conventional adjustment for clustering appropriate, and (iii) when does the conventional adjustment of the standard errors matter.

19 ноября, 15:03

Unveiling the Future of Liberty

Earlier today, I was honored to join Treasury Secretary Jacob Lew and Deputy Secretary Sarah Bloom Raskin to unveil designs for the 2017 American Liberty Gold Coin. The unveiling not only marked a historic milestone for the allegorical Lady Liberty, who has been featured on American coinage since the late 1790s, but also served to kick-off the Mint’s 225th anniversary—a year-long public awareness campaign about its mission, facilities and employees. I am very proud of the fact that the United States Mint is rooted in the Constitution. Our founding fathers realized the critical need for our fledgling nation to have a respected monetary system, and over the last 225 years, the Mint has never failed in its mission to enable America’s growth and stability by protecting assets entrusted to us and manufacturing coins and medals to facilitate national commerce. We have chosen “Remembering our Past, Embracing the Future” as the Mint’s theme for our 225th Anniversary year. This beautiful coin truly embodies that theme. The coin demonstrates our roots in the past through such traditional elements as the inscriptions United States of America, Liberty, E Pluribus Unum and In God We Trust. We boldly look to the future by casting Liberty in a new light, as an African-American woman wearing a crown of stars, looking forward to ever brighter chapters in our Nation’s history book. The 2017 American Liberty Gold Coin is the first in a series of 24-karat gold coins the United States Mint will issue biennially. These coins will feature designs that depict an allegorical Liberty in a variety of contemporary forms including designs representing Asian-Americans, Hispanic-Americans, and Indian-Americans among others to reflect the cultural and ethnic diversity of the United States.​ 2017 American Liberty Gold Coin obverse (left) and reverse (right). (United States Mint Photos)   Rhett Jeppson is the Principal Deputy Director of the U.S. Mint.    

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19 ноября, 14:29

Gaia Pope: sister pays tribute to 'beautiful and wise' teenager

Police say they are confident a body discovered after a search in Swanage, Dorset, is that of the missing 19-year-old The sister of Gaia Pope has paid tribute to her sibling, calling her beautiful, wise and the “absolute light of my life” after the discovery of a body in the search for the missing 19-year-old.The body was found on Saturday afternoon by search teams near Swanage in Dorset, close to where clothing belonging to the teenager was found on Thursday. Continue reading...

19 ноября, 13:00

Saido Berahino: the former golden boy who has gone 632 days without scoring | Barry Glendenning

The Stoke striker, who faces Brighton on Monday, was labelled West Brom’s answer to Harry Kane but is yet to score for his club. Will his touch ever return?It’s a long time, 2,159 minutes. Exactly enough to fit in Beverly Hills Cop and all four Indiana Jones movies, plus the Godfather, Toy Story, Man With No Name and the original Star Wars trilogies. Those of a more masochistic bent could spend it watching all the senior football Saido Berahino has played since he last scored a goal: 2,159 minutes and counting. By the time Stoke City take on Brighton in their next Premier League game, 632 days will have passed since he celebrated one of his own. As statistics go it is shocking and must be a source of great concern for his employers. How many more movie marathons must we sit through before it is fair to label him another wasted talent with a great future behind him?In an interview with the Daily Telegraph in early 2015, Berahino complained that “people read about me and hear about me but nobody really knows who I am”. At the time he was best known as a raw but promising 21-year-old striker with West Bromwich Albion, but the interview sketched a picture of a more complex character, offering different aspects of light and shade. A refugee forced to flee Burundi for England alone as a 10-year-old, Berahino eventually joined his mother and sisters who had also escaped the civil war that claimed the life of his father. He came across as an apparently well adjusted young man who clearly adored his mum and had a good understanding of the suffering those left behind in his homeland were forced to endure. Heck, he was even trying to help by setting up an eponymous foundation which he hoped would eventually raise enough money to build a hospital. Continue reading...

19 ноября, 12:17

Stiff Drinks! 15 of the Strongest Alcoholic Drinks You Can Order

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Sometimes a beer or wine won't cut it. For the days you need a little bit more than a standard beverage, try one of these strong alcoholic drinks.

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19 ноября, 12:00

Unlucky or deluded? One man’s attempt to swim the Atlantic | Alex Moshakis

Ben Hooper’s plan to swim 2,000 miles from Senegal to Brazil – complete with sharks, storms and deadly jellyfish – didn’t work out. Alex Moshakis meets him to find out whyOne sunny morning last November, Ben Hooper, a 38-year-old former policeman, waded into the Atlantic Ocean from a beach in Dakar, Senegal, and plunged right in. In film of the moment, Hooper appears thick set, almost podgy. He’d spent the past year bulking up and now layers of fat concealed muscle beneath. He wore a sports watch, black goggles provided by a sponsor and a pair of tight blue shorts. The sun had risen early, and by 10.33am, when Hooper entered the water, the ocean temperature had reached 30C, a lukewarm bath. A group of reporters gawked from the shallows. Most of them squinted in the bright light.Hooper had been in Dakar for six weeks, preparing to swim to Natal, northeast Brazil, 1,879 miles away. If successful, he would become the first person to swim across the Atlantic Ocean – 12 miles a day for over 140 days straight – an unfathomable feat. As he swam away from the beach, Hooper began to feel tears in his eyes. A mile later he “cried like a baby”. The launch represented the culmination of three years’ planning, and the relief was overwhelming. Later that day, as the adrenaline wore off and the magnitude of the task began to sink in, he swam against currents that made it difficult to achieve significant mileage. Later, while he recovered on the support boat, a 37-year-old catamaran, he wrote the first in a series of blog posts he’d publish during the attempt. “Spent the night drifting under sea anchor,” it read, “4.5 miles closer to making history.” Continue reading...

19 ноября, 10:33

Tasty Ways to Make Cinnamon Rolls Even Better

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Cinnamon rolls are great as they are, but these 7 recipes turn "great" into "absolutely amazing."

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19 ноября, 10:02

Alcohol detected on breath of U.S. serviceman after fatal crash in Okinawa

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Police detected alcohol from a U.S. serviceman after a military truck he was driving collided with a light truck, leaving the Japanese driver dead, in Okinawa Prefecture on…

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19 ноября, 10:00

Naked attraction: art and tragic tales in Modigliani’s Paris

As Tate Modern prepares a new exhibition of his work, including 12 of his famous nudes, Louise Roddon explores the artist’s haunts in Montmartre and MontparnassePoor Amedeo Modigliani, what a tough life he led. I’m thinking this as I climb the steps to his last studio in Montparnasse. It’s a classic artist’s garret with peeling paint and poor lighting, and climbing the countless floors on a narrow stone tread, leaves me winded. It wouldn’t have been easy for a man with advanced tuberculosis. With Tate Modern about to stage its Modigliani exhibition, I’ve come to number 8 Rue de la Grande-Chaumière, his final home before he died tragically young in 1920. At 35, he wasn’t just a victim of TB, but was suffering the toll of a lifetime’s enthusiasm for alcohol and drugs. Continue reading...

19 ноября, 08:41

26 of the Most Nagging Hollywood Stars

Some actors and directors have earned a reputation for being difficult to work with. Here's a look at 26 of the most demanding Hollywood stars.

19 ноября, 08:00

Palestinians warn they will freeze US ties if PLO office closed

The US state department announced its decision to close the Palestinian Liberation Organization (PLO) office late last week, citing a 2015 law placing conditions on the US mission office. It's hoped a meeting on Monday between the US Department of State and the PLO will shed light on the Trump administration's decision to close the PLO diplomatic office in Washington, DC. The planned closure of The PLO office in Washington prompted shock and a threat from a senior Palestinian official to freeze ties with the US. The move has strained relations between the US and Palestine at a time when the administration claims it is attempting to reinvigorate the Palestine-Israel peace process. Al Jazeera's Diane Eastabrook reports from Washington, DC. - Subscribe to our channel: http://aje.io/AJSubscribe - Follow us on Twitter: https://twitter.com/AJEnglish - Find us on Facebook: https://www.facebook.com/aljazeera - Check our website: http://www.aljazeera.com/

19 ноября, 04:46

The third option, by Scott Sumner

Last week I attended the Cato Monetary conference in Washington. Jim Dorn always does a good job of finding interesting speakers. I couldn't help contrasting the event with the Peterson Institute conference that I attended last month. At the Peterson Institute, most speakers correctly noted that insufficient AD was a key problem over the past decade, but also argued (wrongly, in my view) that monetary stimulus was relatively ineffective at the zero bound. At Cato it was almost the exact opposite. I don't recall anyone doubting the effectiveness of monetary policy (I attended 3 of the 4 panels), but there was almost no concern about insufficient nominal spending. Indeed a number of speakers seemed worried that policy was too expansionary. This makes me feel really good about the prospects for market monetarism. Both logic and facts are overwhelming on our side. It seems absurd to claim a fiat money central bank could not debase its currency. Are the Zimbabweans really that much more talented than we are? And when countries like Japan have changed policy the yen has fallen sharply, even at the zero bound. That doesn't happen in the Keynesian model. As for the level of AD, during most of the past decade both inflation and employment have been well below the Fed's targets. It's the (conservative) opponents of monetary stimulus who have a difficult argument to make, not us. This recent article gives a good sense of the weakness of the arguments of our opponents: TOKYO (Reuters) - Premier Shinzo Abe's victory in last month's election may make it difficult for the Bank of Japan to dial back its radical stimulus next year despite the rising cost of prolonged monetary easing, former BOJ board member Sayuri Shirai said on Friday. . . . Shirai said the BOJ should start withdrawing stimulus by hiking its yield target and slowing asset purchases next year, given the rising cost and diminishing returns of its policy. "When the economy is in good shape like now, the BOJ needs to normalise monetary policy so it has the tools available to fight the next recession," Shirai told Reuters. "But the election result has made that difficult," she said. Raising the BOJ's 10-year government bond yield target could trigger an unwelcome yen rise by narrowing the interest rate differentials between Japan and the United States, Shirai said. This quote exhibits a basic lack of understanding of monetary economics. The speaker implies that tightening monetary policy gives the BOJ more "tools" to fight the next recession, whereas the exact opposite is true. When the BOJ tightens monetary policy the natural rate of interest falls. The speaker presumably believes that what matters is the gap between the actual rate of interest and zero, whereas what really matters is the gap between the natural rate of interest and zero. When the BOJ raises the actual interest rate with a tight money policy, the natural interest rate falls. If Shirai were correct, then the Fed could have raised interest rates to 20% in 2008, giving them lots of "tools" to later cut rates and spur the economy when the recession got severe. But that's about as effective as trying to pick yourself up by your bootstraps. This is why I insist that people appointed to the Fed should be experts on monetary economics. I don't care about credential---it makes no difference if they have a PhD---but they need to understand the basic principles of monetary economics. Does Japan need higher interest rates to pop asset prices bubbles? Consider the Japanese stock market, which is about 40% below the peak value in 1991, while the US market has risen almost 10-fold. Or take housing, where prices in Japan are down about 40% since 1990 (lavender line), while they have risen 140% in the US (blue) and 360% in Australia (light blue). Australia's had the highest interest rates over that period (among developed countries), and Japan has had the lowest. So no, rapid asset price increases are not caused by low interest rates, indeed asset prices tend to rise more rapidly in countries with very high nominal interest rates. Japan doesn't have to worry about asset price bubbles. Japan would benefit from higher nominal interest rates, but only if brought about by a more expansionary monetary policy. PS. I should emphasize that there was plenty that I agreed with at the Cato conference. A number of speakers were critical of the war on cash (as am I), and Charles Calomiris was skeptical of the view that China was a currency manipulator. PPS. David Beckworth presented me with a coffee mug. Market monetarism is right on target to becoming the dominant view in macroeconomics; just give us another 10 or 20 years. (5 COMMENTS)

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19 ноября, 04:37

How the Russian Army Learned to Wage War (and Kill Its Enemies)

Michael Peck Security, Europe History teaches valuable lessons to Moscow's military planners.  The lessons learned section of a U.S. Army analysis of urban warfare is mostly a no-brainer: urban combat is long, costly, burns out troops and resources, combined arms warfare is essential, and so on. Lessons that many armies, competent or not, have realized after scores of city fights going back to Stalingrad and Hue. But what particularly interesting about this study by the U.S. Army’s Asymmetric Warfare Group is how Russia learned to fight in cities. The study, titled “Modern Urban Operations: Lessons Learned from Urban Operations from 1980 to the Present,” examined ten urban battles, including three fought by Russia. The report was published in November 2016 and recently released on the website Public Intelligence. The disastrous Russian assault on Grozny in 1994 is an example of how not to fight in a city. A relatively small Russian force of 25,000 men attempt to storm key buildings in Grozny. The Russian tank and mechanized infantry columns were picked off and destroyed by small teams of Chechen fighters armed with light antitank weapons and sniper rifles, and taking advantage of the urban terrain for cover and concealment. What a War Between America and China Would Look Like.  The U.S. study faulted Moscow for a lack of information operations to win over the Chechen populace and prepare the Russian people for the conflict. Russian troops failed to “maintain proper command and control of their columns moving through the streets of Grozny.” Russian commanders employed reconnaissance units but didn't support them, which resulted in the scouts having to fight instead of reconnoiter. What a War Between NATO and Russia Would Look Like.  Read full article

19 ноября, 03:44

Zap Away Cellulite With These Simple Exercises

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Cellulite is a pain -- but you aren't totally stuck with it. Take control of cellulite by using these simple exercises to tighten your glutes and thighs.

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19 ноября, 03:28

Hammond: Driverless cars will be on UK roads by 2021

The chancellor says the country must embrace new technologies in order to succeed.

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19 ноября, 03:05

Bryan Cranston: Breaking good… TV star electrifies the London stage | Andrew Anthony

In the hit TV series, he made his name as a master of transformation and the same could be said of his career. Now he has become the latest US actor to light up British theatreThe American actor Bryan Cranston received rave reviews last week for his performance at the National Theatre in Network, the stage adaptation of the Oscar-winning film from 1976 that starred Peter Finch and Faye Dunaway. Just as American film and television can’t seem to get enough of British theatre-trained actors, so we return the favour, with no one lighting up the London stage quite as much as an American screen star.Although most of his acting career has been spent in either obscurity or overlooked supporting roles, and although he won a Tony Award for his portrayal of Lyndon B Johnson in Robert Schenkkan’s All the Way, Cranston is indeed a screen star – thanks to his celebrated role as Walter White, the chemistry teacher-turned-drug lord, in the cable hit Breaking Bad. Continue reading...

18 ноября, 22:59

Stuart Hogg and Scotland denied at the last as New Zealand hold on

• Scotland 17-22 New Zealand• Impressive Scots just miss out on first win over All BlacksThis was an extraordinary attempt to overturn 112 years of hurt – and for a moment Murrayfield, with their darling Stuart Hogg streaking down the left in the last seconds, thought they might have the glory, at last, of a win over New Zealand. Alas, it was not to be, but this was their most valiant attempt for more than 30 years. How they played from the off, and more than that, how they played till the very end. They looked for long periods – including nearly all of the first half – by some distance the better team. Related: England waltz away from Australia as Danny Care completes smash and grab Continue reading...

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18 ноября, 21:14

Sunderland serve a dark reminder to Chris Coleman of a Light dimmed

Club’s ninth manager in six years has an in-tray stacked with woe after a record failure to win at home underlines his taskAs Chris Coleman packed a suitcase and prepared to become Sunderland’s ninth manager in six years, his new players issued a reminder of the grisly challenge facing the former Wales coach.Perhaps mercifully, Coleman – who will be formally unveiled on Monday and take charge of the team at Aston Villa on Tuesday – did not arrive on Wearside in time to see the club set a thoroughly unwanted record. Continue reading...

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18 ноября, 20:25

8 Surprising Amazon Prime Perks That Can Save You $52 or More

Free, two-day shipping aside, here are some lesser-known perks of being an Amazon Prime member. Get the most bang for your 99 bucks.

04 декабря 2014, 15:20

Саудовская Аравия с января 2015 года снижает поставочные цены на нефть для США и Азии

ЛОНДОН, 4 декабря. /ТАСС/. Саудовская Аравия с января 2015 года снизит поставочные цены на нефть для США и Азии. Об этом сообщает агентство Bloomberg. Стоимость нефти Arab Light снижена на $2 за баррель. Как ранее сообщал Wall Street Journal со ссылкой на источники, Саудовская Аравия не намерена сокращать объемы добычи нефти и рассматривает в качестве допустимой для себя цену барреля Brent в $60. Крупнейший производитель нефти в рядах ОПЕК Саудовская Аравия считает, что нефтяные цены способны стабилизироваться в районе $60 за баррель. Эр-Рияд и другие страны Персидского залива уверены, что способны выдержать этот ценовой уровень", - пишет издание. Страны Персидского залива не установили для себя определенную целевую цену барреля, и если она упадет ниже $60, то длительное время на данном уровне не продержится, говорит источник WSJ. По мнению источников газеты, нынешний подход Саудовской Аравии означает, что в ближайшей перспективе она не пойдет на сокращение добычи, даже если цены на нефть продолжат падение. Глава "Роснефти" Игорь Сечин также допускает, что цена нефти может упасть до $60 за баррель и ниже в первой половине 2015 года. В интервью австрийской Die Presse, опубликованном 27 ноября, он отметил, что у "Роснефти" достаточно запасов и места для маневра.