The Daily Cow

What does it mean when a survey reports that there is a margin of sampling error of plus or minus 3%? Why not four, or two? Certainly it's possible for the sample to be off by more than 3%, so stating the sampling error (without specifying the corresponding level of confidence) is simply misleading the audience into a sense of false confidence, because in reality, "there is a margin of sampling error of plus or minus 3%" means "we're pretty sure we're correct to 3%, but good luck if you want to know how sure!"

Every assertion of a specific margin of sampling error in surveys must be accompanied by the corresponding confidence level so that the public can see a more informative survey and develop a more realistic understanding of the survey results. If there is a standard (95%, maybe?), publish that with each survey; otherwise, develop a standard.

Gallup, you start first.

You know when you're buying those 300 dollar stereos and the salesman tries to sell you a 50 dollar service agreement--so if it breaks they will fix or replace it? Have you ever purchased the offer before?

What do you think are the realistic chances that your 300 dollar stereo will break? If you're paying 300 dollars, you'd better hope they will work up to three years. If they're not, you should question why you're even paying 300 dollars for the thing; but if they are, you have no need for the service.

Retailers (and lots of other businesses) make a significant portion of their profits from these agreements. These are easy on them (comparatively few people will actually require a full replacement or repair, and even fewer will actually take the time to go through customer service) and extremely high-margin.

So unless you're extremely risk averse (if you'd take 10 bucks over the equal chance of losing 10 and getting 100), avoid these scams because otherwise, you lose if the product fails, and if the product doesn't.

Remember Blackbird? Now there's a website for black people to find black jobs for black people! Why do they need their own website anyway? There's no asiancareers.com.

The question was the following:

Consider a setting with three bidders and complete information where bidders' values are commonly known. There is a sealed-bid auction where the highest bidder wins the object and pays the AVERAGE of the all three bids. In the case of a tie, the lowest-indexed of the high bidders wins the auction and pays the average. Suppose v1 > v2 > v3. In any Nash equilibrium does player 1 win the object?

And the choices were: (a) For some v1, v2, v3 and (b) For all v1, v2, v3.

The use of "any" in this context confused me. I thought it meant that, for a given values v1, v2, v3, if there was any Nash equilibrium where player 1 wins the object, the condition is satisfied for the given values. Apparently any meant all! My professor says it means that given the values, player 1 must win the object in all the Nash equilibria (which is certainly not true).

I am more familiar with (and prefer) determining whether ∀i∃j such that P(i,j) is true or false. It avoids the confusion between any and all (apparently they mean the opposite of what I thought they meant), is more concise, and is language independent.

I never seem to get more than half of True/False questions right. Either I circle the wrong thing, or my intuition is tricked by the wording. Since they are not usually worth too many points I neglect to go through a proof of my answer, and consequently I choose the wrong one. The problem is intensely magnified when the consequences of missing a question is the loss of twice (or five times) the value of the entire problem (say, losing 10 points, as opposed to getting nothing, on a 2 point problem).

In a NYT article esteemed NYU Stern professor Nouriel Roubini discusses the falling prestige of the dollar and the inevitable elevation of the Chinese RMB to the world's de facto reserve currency. In attempting to adapt his explanations to the general public, he completely butchers his reasoning, and instead says something completely wrong.

He claims that "we have been able to issue debt in our own currency rather than a foreign one, thus shifting the losses of a fall in the value of the dollar to our creditors," forgetting that an external cost such as currency exchange loss or gain is incorporated into the demand-and-cost calculations of the buyer and the seller, in expectation. That is, since foreign investors knew that there was a possibility of a currency loss, the demand was adjusted accordingly to the expected return with currency fluctuations priced in (plus some factors for risk aversion), so the seller (US Government) would be facing a weaker demand than would have been the case for a safer environment.

He then claims that "waving commodities priced in dollars has also meant that a fall in the dollar’s value doesn’t lead to a rise in the price of imports," which is another form of the same mistake--forgetting that in expectation, the currency is just a veil. In economics terms, if it costs me 20 Pounds to produce a barrel of oil when teach dollar bought exactly a pound (making oil 20 dollars/barrel in cost for me), it does not still cost me 20 dollars/barrel when the dollar is worth 50 cents. Assuming other costs are constant, the cost of oil production in a local currency still being 20 Pounds/barrel, the cost has risen to 40 dollars/barrel.

Therefore, Americans are not immune to the effects of dollar devaluation and currency loss, as economics professor Nouriel Roubini claims.

I post so much more when I have finals to study for, essays to write and projects to complete.

Today, [something happened]. Then, I realized that/turns out [what I said in the previous sentence is a lie]/I proceeded to [do something extremely tragic]. [Fragment of WTF-ness]. FML

Examples:

Today, I woke up after a night of partying and went to the bathroom. That’s when I realized that after passing out with my shoes on last night, my friends decided use a black sharpie and play “connect the dots” with my acne. FML

Today, I finally beat the song "Through the Fire and Flames" on Guitar Hero 3. I then realized that it was the biggest accomplishment I've ever made in my entire life. FML

Today, I decided to shave my legs completely to be more confident in my dress. I spent over an hour making sure my legs were perfectly shaved. It wasn't until I had been out awhile that I realized I forgot to shave my armpits. FML

Today, the girl I like called me and said she liked me. After I told her I liked her too, she didn't say anything. Thinking the call was a joke, I started screaming at her and calling her a slut. Turns out it wasn't a joke, she had just hit mute on her phone by accident. FML

Today, I was walking to find a public toilet in a Chinese village. While looking for the women's restroom, I stepped on a thin sheet of plastic. I proceeded to fall into the toilet's waste collection area and found myself knee-deep in the villagers' faeces. FML

... etc

They're all the same. I think FML stands for Formatted Markup Language.

There was an earthquake here this afternoon, but there was no way I could've felt that given how loud my upstairs neighbor is. When he stomps, the entire building trembles. And he stomps a lot.

Why do people say DVD Disk, LCD Display, CMS System, PDF File, IRC Chat, GMT Time, DC Current, HIV Virus, and PIN Number?