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hackerblues

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Productivity be damned, RTO makes fiscal sense when you have a 15 year lease on a building you can't get out of. I don't agree with it, but I can see why you'd want warm bodies in seats when you pay 20,000 (or more) a month for your modern-tech cube farm.

Could you explain your thinking this further, please?

In your example the company is paying for accommodation whether it is used or not, it seems to be a sunk cost. The fiscal decision making should hinge purely on what gives the best ROI given that money has already been forsaken.

What you're describing seems to be more aligned to "it makes sense psychologically." A large and very visible commitment has, due to unforseeable reasons, been made partially unnecessary. Following through regardless saves face.

I'd be interested to know if you might be able to if you could find problems by looking at invariants over partitions of the space.

Like

Is the number of solutions with v1=false plus the number with v1=true the number with v1 free?

If we have n constraints then there 2*n variants where you negate subsets of constraints. Is the sum of solution counts over the 2*n subproblems equal the size of the variable space?

It was an accomplice who used the information.

"Mr Obama's senior science and technology adviser John Holdren had his personal accounts hacked and Gamble passed all of his personal details to an accomplice who used them to make hoax calls to the local police claiming that there was a violent incident at Mr Holdren’s house resulting in an armed swat team being deployed."

I of course have no idea what the real answer is, but if you play out the hypothetical this is hardly a paradox.

NK hacks Sony. US uses technique x to attribute the attack to NK. In the course of a shared investigation NK learns what technique x is. NK changes their future operations to counter technique x. The US loses the ability to use technique x to attribute attacks.

In your jewellery store example I think it may be reasonable to prosecute the person.

In increasing levels of seriousness:

1. The person is walking by the store and, in the course of their everyday activity, sees that the door is ajar; they then contact the owner. This seems fine to me.

2. The person is walking by the store, sees the door ajar, and then altering their normal activities decide to actively test the door to see if they can break into the store; they can and then contact the owner. This seems dodgy to me.

3. The person chooses to visit each jewellery store in town to see if any have a door ajar. This definitely seems inappropriate.

The reason I come down opposed to the person in the second example is two-fold.

Firstly, ignoring intent, where do you draw the line on an acceptable level of 'break the security' activity?

- Thinking that the door is ajar and pushing on it?

- Seeing that the lock is vulnerable and picking it?

- Finding a ground floor window and breaking through it with a brick?

The resolution I choose is that if you have gone out of your way to subvert the security of my stuff without my consent then you have crossed the line. Gray is black.

Second, I don't care about your intent. Every security system will break at some point, and so I view the existence of doors and locks as mainly being about roughly outlining the boundaries that I expect to be respected. If I want to improve my security then I'll hire someone to advise me on how to do it. If I come home tonight to find a stranger who has broken into my house in order to prove that it's possible then (1) I already know, and (2) they have just caused the harm which they are nominally trying to protect me against.

My argument is that the public paying for a thing is not sufficient grounds for claiming that the public should have use of that thing.

Since knowledge creation and nuclear weapons are both examples of things which the public pays for, I defend the comment as it stands. The distinction between IP and physical property does not enter into the claim.

[BACKGROUND INFORMATION]

When a person makes a claim like "All X's are Y's" then it is sufficient to provide a single example of an X which isn't a Y to demonstrate that the claim is false. The example is referred to as a counter example.

[THE CONTEXT]

The most reasonable interpretation of the previous commenter which I could identify was:

"When the public pays for knowledge to be created, it should be that the public owns the knowledge it paid for...[but it is expect that] the public that paid for it, [must] pay more and more [to use it]."

To restate this in the counterexample language

(1) 'All [things which the public pays for] are [things which the public owns]'

(2) 'All [things which the public owns] are [things which the public should be able to freely access and use]'

Which combine to produce the claim

(3) 'All [things which the public pays for] are [things which the public should be able to freely access and use]'

with "knowledge" being one of the things which the public pays for and so "knowledge" being one of the things which the people should be able to freely access and use.

[MY ARGUMENT]

In order to demonstrate the flaw in this claim as just presented#, I brought up nuclear weapons as a counter example. It is an instance of something which the public pays for but of which the public shouldn't have free access to and use of.

[MY POINT]

In order to maintain the truth of the claim the previous commenter must show that my example is not a counter example by arguing that the public should have access to/use of nuclear weapons.

Alternatively, they can agree that the claim as presented is false, and then perhaps provide a different argument for the conclusion that 'the public should get use of the knowledge created.'

---

I hope this clarifies the point which I am trying to make. Regretfully, the hyperbolic inclusion of nuclear weapons plays a key role my argument and so I did not remove it.

---

# I acknowledge that my interpretation of the claim may not have been what the author intended. Statement (1) seems to be strongly implied by the author, but (2) is inferred. The role of the questions in my original reply was to draw out a precise explanation of what ownership entails. But certainly in the case of "knowledge" the person want to be able to access and use the knowledge.

The public's taxes also fund the military. Extending your principle to this case implies that the public owns the countries nuclear arsenal. Can you advise what this ownership should practically entail? Should I get access to the weapons? Should I be able to use them? Or am I limited to indirectly benefitting from their existence?

If you're trying to gain information and experience then it is silly to try to optimise for "How many pages have I looked at?"

You need to come to terms with what the author is claiming, critically evaluate the argument used to support those claims, and then decide the relevance of this new perspective on the world (eg, how will you implement it in your life?)

This all takes time.

I believe the previous commentator was referring to the work conducted by Latanya Sweeney

http://dataprivacylab.org/projects/identifiability/paper1.pd...

"In this document, I report on experiments I conducted using 1990 U.S. Census summary data to determine how many individuals within geographically situated populations had combinations of demographic values that occurred infrequently. It was found that combinations of few characteristics often combine in populations to uniquely or nearly uniquely identify some individuals. Clearly, data released containing such information about these individuals should not be considered anonymous. Yet, health and other person-specific data are publicly available in this form. Here are some surprising results using only three fields of information, even though typical data releases contain many more fields. It was found that 87% (216 million of 248 million) of the population in the United States had reported characteristics that likely made them unique based only on {5-digit ZIP, gender, date of birth}. About half of the U.S. population (132 million of 248 million or 53%) are likely to be uniquely identified by only {place, gender, date of birth}, where place is basically the city, town, or municipality in which the person resides. And even at the county level, {county, gender, date of birth} are likely to uniquely identify 18% of the U.S. population. In general, few characteristics are needed to uniquely identify a person."

The way you are talking about jargon in mathematics suggests you have a limited experience of what mathematicians do. Here's an illustrative example of mathematics as done by mathematicians.

~~~~~~~~~~~

Define: An integer n is `even' if there exists some integer m such that n = 2m.

Theorem: For any two even integers n and a, the sum n + a is an even integer.

Proof: Since n and a are even there exist integers m and b such that n = 2m and a = 2b. Now,

  n + a = 2m + 2b; by assumption
        = 2(m+b); by the distributive property
        = 2z; for the integer z = m+b
Therefore there exists some integer z such that n+a = 2z. Hence n+a is even.

~~~~~~~~

That is to say, in mathematics we introduce some definitions/gibberish/jargon (in this case `even') and then we use logic to reason about the implication of our choice of definition (the sum of even integers being even.)

The important thing is that the definition plays an essential role; definitions are the building blocks on which all of mathematics operates. To emphasize: if you strip away the definitions you literally have nothing to build on - we can't apply logic to nothing and arrive at something.

This leads to the point I made in my earlier comment: the reason we need definitions rather than intuitive explanations is that you can't logically reason about a concept unless you nail down the relevant details of what that concept is exactly. We can't do the 'proof the theorem' part of the above example.

So how does mathematics then fit into application?

Guy 1: In this basket I have as many stones as I have fingers and in that basket I have as many stones as I have toes. For each basket I can pair up the stones so that each has a partner. Will this still be the case if I combine the stones from each basket?

Mathematician: Well, lets represent the number of stones in each basket with the integer 10. Pairing stones corresponds to the integer being even and combining the baskets corresponds to adding the two integers. I note that 10 is even since 10 = 2x5 and so I can apply my theorem to conclude that the sum 10+10 is even. Thus I conclude that when you combine the baskets you will still be able to pair each stone with a partner.

Guy 1: Wait, wait, wait! I don't understand this 'even' jargon. Do it again without the jargon.

Mathematics: The definition of 'even' was central to my whole processes. Without it I can't even set up the problem, let alone apply the theorem used to justify the answer. I could perhaps just give you an answer, "MATHEMATICS SAYS YES", but then you wouldn't be able to repeat it yourself for different numbers of stones.

If the above is understood then I can quickly address the claims you have made.

> it's better to generalize upwards from reality and actual use cases instead of starting utterly removed from reality and trying to apply the generalizations downwards.

Mathematics is generalisation utterly removed from reality. This is why we have "Adding integers" and not "Adding together collections of dogs" and "Adding together collections of apples" and "Adding together collections of hats" and ...

> Sure, it's convenient for a mathematicians to be able to use shorthand gibberish to talk to other mathematicians.

Mathematics is the practice of defining new gibberish and then reasoning about that gibberish. The gibberish isn't a shorthand for something, it is the thing.

> It doesn't justify pushing this jargon on other fields.

Mathematics is definitions/gibberish/jargon. Applying mathematics to a field thus means applying definitions/gibberish/jargon to that field.

> When it comes to a point where gibberish becomes the only way to explain mathematical abstractions, then you should step back and ask yourself "where the hell did this go wrong?".

At least since Euclid's formulation of geometry.

>> So by the intuitive explanation we can make this single line any dimension that we want. > And if this makes sense in the given context - sure, why not?

The problem is that it doesn't. Your explanation of an n-dimensional space is more a description of the larger space in which our space of interest is embedded.

In all instances the space (the line) remains unchanged, the only thing which changes is how we are describing it. For the dimension of the space to be a property of the space it needs ignore how we choose to describe it.

I certainly agree that an intuitive understanding of a concept can be helpful as a guide and emotionally satisfying. However, I don't think that it is at all sufficient and it is precisely "mathematical gibberish" which resolves the problem.

An isolated concept is worthless. It is only when you are about to apply it by reasoning with it that becomes valuable. The problem with intuitive explanations is that they don't nail down enough details to allow a person to reason with them.

"I think of points in an n-dimensional space as objects holding n different types of information"

Imagine walking into a room and drawing a straight line on the floor. What is the dimension of that line?

Answer = One dimensional. Proof: We can describe each point by one type of information. Point = (Distance of that point from the start of the line.)

Answer = Two dimensional. Proof. We can describe each point by two types of information. Point = (Distance of that point from the East wall, Distance of the point from the North wall.)

Answer = Three dimensional. Proof: We can describe each point by three types of information. Point = (Distance of that point from the East wall, Distance of the point from the North wall, Distance of that point from the roof.)

Answer = Four dimensional....

So by the intuitive explanation we can make this single line any dimension that we want.

This isn't just a problem within mathematics. For a simple programming example:

Question: How does a computer program work?

Intuitive Answer: You give the computer a list of instructions for it to carry out.

Result: The guy opens up notepad and types in "Make a computer game where I walk around shooting Zombies."

I believe that a common problem for people who are proof reading documents is the brains tendency to complete patterns based on partial information. This causes a person to read not what is actually written but instead what they expect to read.

For example, if you had seen the cliched sentence "The cat sat on the mat" tens of times over your lifetime then you might tend to skim ahead and miss the mistake in "The cat sat on the met."

One approach to reduce this problem is to consciously direct your attention in such a way as to reduce your own expectations. Some common tactics include:

1. Take a break in between writing the text and editing it. The common advice for writing essays in school is to leave your draft shut up in a drawer for a few days before returning to it.

2. Examine each word in the text in a way which separates it from the context of the sentence it is written in. You could do this by physically pointing at each word with a finger/pen as you read it, or by reading the text backwards from the last word to the first.

The above might increase your ability to spot a spelling mistake but will do little to assist whole-sentence grammatical mistakes. My best advice for that task is to read the text out loud. I find it much easier to hear such a mistake than to see it.

For the problems with reading you might wish to do some research on "active reading". Reading with a question in mind can help you to properly concentrate on the material.

The question might relate to a specific piece of information, eg skimming through a tutorial to discover "What arguments does the make_widget command take?"

The question could also be focused on the structure of the text, eg "What is the main idea of this paragraph?", "How could I rewrite this complicated sentence in my own words?", or "How does the evidence introduced in this paragraph relate to the claim stated at the beginning of the chapter?"

I didn't know how cheaply a laptop could be purchased for so I just checked on Ebay for Used/Refurbished laptops. Currently there are 47 'Buy It Now', nominally complete and working, laptops/netbooks available for $40-60.

They all looked pretty crappy, is it reasonable to assume they are all stolen property on the basis of their price alone?

Surely the context of the filming is important though. If he had gone into the bathroom and was filming people using the toilet then it wouldn't be enough that "He was given permission to film the yellow badge people. On his lunch break. Using Google equipment."

There are three components.

Generation -> Grid -> Homes and Business

It is possible to change the type of generation without having to change the way electricity is taken out of the grid to power things. This makes it easier to make changes in the type of generation. Changing from coal to solar to nuclear just involves making a new connection between the power plant and the grid. Everything else then just works as normal.

By contrast, if we converted energy into "Dragon Tears" instead of electricity we would need to lay down a whole new Dragon Tear distribution network so that people could use that energy. Then, a scientific break through occurs and we are able to use the much more efficient "Unicorn Blood". But now we have to rip out the Dragon Tear distribution network and install a new Unicorn Blood network.

For people who aren't up to speed on Abstract Algebra, the analogy to have in mind is:

A: Rectangles and squares are the same things.

B: That isn't correct. All squares are rectangles but the reverse isn't true.

A: I only care about the number of sides the polygon has so for my domain of interest rectangles and squares are equivalent. (Therefore the falsity of the first statement is a minor issue?)

My background as a mathematician likely biases this answer. Someone who has experienced life outside of academia will likely have different advice.

The mathematics you will likely want to know includes:

- Multivariate Calculus/Matrix Stuff/Linear Algebra

- Real Analysis

- Probability

- Measure Theory?

- Statistics 101

If you successfully took proofs-based mathematics courses in undergraduate and you've grokked "mathematical maturity" then learning these subjects is just a matter of time. These subjects for the basics tools for dealing with classical statistics.

I'm not currently engaged in research but there seems to be a few major trends in the talks I've attended.

- It appears that the Frequestist approach to finite dimensional models with small sample sizes is largely resolved.

- The introduction of high powered computing gave new life to the analytically intractible Bayesian approach and has renewed interest in how to to Monte Carlo simulation more efficiently.

- There has been a lot of work studying situation where the number of parameters is infinite or at least significantly larger than the number of samples. Eg, determining 10,000 genes from each of five people with cancer and five without and trying to identify which gene causes cancer.

- Perhaps this is more machine learning but there has also been interest in how to deal with unstructured data. Traditionally the random variables have been numbers so you can say things like "Assume a citizens height is normally distributed with mean x and variance y." It's a bit more tricky to meaningfully put a distribution on the set of all email texts, or the set of all network structures etc.

- There also appears to be interest (on blogs at least) about data visualisation.

The point of mentioning all of these is to point out that there are a number of options available to you. Some are more pure mathsy and other more computer sciencey. Different topics will require different mathematical backgrounds.

The aspect of university which can be replicated in self study is the aquisition of knowledge from a source. Regardless of the source, your professor saying "Display text in Python with the 'print' command." or you reading it in a book, you will need to put in the same mental effort to learn it. This process is the core aspect of education.

What university provides is a number of side things which assist in this process.

1. An expert in the field who can advise you from experience what information is important, where the best information sources are, and in which order to approach things.

2. Feedback on how well you understand the material via discussion groups, assignments and examinations.

3. The opportunity to ask questions about the material.

These sound cliched but they are really important. The alternative is a person who is doing something in an inefficient way because they don't know the better way, they don't even know that there is a better way, and the answers they are producing are incorrect because they are blindly applying the inefficient method when it doesn't work in this case.

University also provides access to credentials through grades and letters of recommendation, a network of peers who will likely end up in a similar industry to you, and various social/clubs things.

My advice would be to pick courses with these advantages in mind.

- Do I know how I would learn this field? Maybe the topic is so large or new that there is no standard text and you will need a guide.

- Could I obtain easy feedback if I self-studied? You can check arithmetic on a calculator but it's harder to look at a piece of your writing and know if you are improving and what needs correction.

- Do I want to build connections with this industry? Selling software to engineers might be easier if you know something about the domain, and know some engineers who can vouch for you and tell you what problems they have.

"I think that part of the problem is that there's inflation in upvotes because people have an unlimited supply."

It's not obvious to me that this is true. Here is a counterexample:

In the extreme case, if the user base consisted of a set of 'wise old users' who only up voted the 'good' content and a set of 'mindless new users' who literally up voted every post, then the votes from the latter group just add to the baseline vote count without having any power at changing the orderings of submissions. In this situation the submission ranking is determined solely by the 'wise old users' even if they are greatly outnumbered.

~~~~

The problem you describe is that the new people are interested in different things to the old and can use their number advantage to push things in that direction.

It seems to me that there are a few possible solutions.

1. a) Restrict the topics of discussion on the website by restricting the people who can add to the conversation. Eg, disallowing new accounts to be created or starting a new website and only selectively inviting people.

1. b) Restricting the topics of discussion on the website by empowering a certain subgroup of people who share a particular interest. This could be done by moderators deleting submissions or via your suggestion of having 'super votes'.

2. a) Allow free submission of topics but provide manual mechanisms for organising the information better so people can choose the subset that they are interested in. Eg, the subreddit approach or having comments marked as insightful/funny/etc.

2. b) Allow free submission of topics but provide personalised rankings tailored to each user. Eg, user rlpb tends to like posts which RiderOfGiraffes likes and also posts which include the word "thinking" so give those a bonus in the rlpb ranking.

In my opinion the ideal solution is 2.b. I dislike the 'elitist' philosophy of 1.a and b, they seem unworkable as long term solutions and pragmatically if I can find the information useful to me on pages 1 and 2 I don't care if pages 3-100 are junk.

Option 2.a seems to work ok on Reddit. However, it does rely on people playing by the rules and probably also a willingness to subdivide subdivisions quite liberally.

I'm sure there are problems with 2.b as well: people need to be actively providing information about their interests to get the classification benefit, and the computational load is likely higher.

tldr: The premise of any vote based ranking site is that there is one set of universally accepted 'good content.' The success of this mechanism depends crucially on the homogeneity of the population it is applied to. If this assumption is broken it can be re-established by exiling part of the population or segregating the population into more homogeneous subgroups (explicitly or invisibly.)

I see computers as addressing a different part of the problem.

Lets take as a given that people need a way to recall pieces of information for use in the future.

1. Initially people would probably just wander around aimlessly and hope that their natural capabilities would be sufficient. Apparently this was not the case.

2. To reduce these short comings people developed memory techniques to better organise the information to be remembered. By chunking pieces of information in mnemonics and associating facts to these memory journeys they were better able to remember them.

3. Next people developed the technology of writing. This tool had a number of advantages over the previous techniques: less effort was required to store the information, it maintained its accuracy over a longer period of time, and the information didn't need to be recorded (memorised/written) by the person who would need to use it in the future. The method also had disadvantages: this new external form of memory required the person to take something extra along with them, as the number of pieces of information became larger it becomes harder and harder to sort through them to find the correct piece whereas the human brain doesn't seem to become as `distracted', and the individual pieces of information become less connected.

4. I see technology as helping to reduce these disadvantages. The internet means I can check email from any computer in the world and not just at the one computer it was composed at. Search engines assist in finding a particular piece of information within a greater body of information. I am not aware of a great example of information synthesis but I suppose that certain parts of text mining are making steps in this direction: eg, sentiment mining Twitter or trend detection.

I think you can get daily summaries quite easily, eg:

http://www.google.com/finance/historical?q=NASDAQ:GOOG

and from memory when the markets are open you can see the order book stuff:

http://finance.yahoo.com/q/ecn?s=GOOG+Order+Book

But I believe you have to buy the more detailed data from the exchange itself. I have no idea how you do this but as far as I know it costs maybe a few thousand per month.

So more stuff:

http://www.statslab.cam.ac.uk/~chris/links.html