Why programmers work at night [This essay has been expanded into a book, you should read it, here] Image via Wikipedia A popular saying goes that Programmers are machines that turn caffeine into code. And sure enough, ask a random programmer when they do their best work and there’s a high chance they will admit to a lot of late nights. Some earlier, some later. At the gist of all this is avoiding distractions. I think it boils down to three things: the maker’s schedule, the sleepy brain and bright computer screens. The maker’s schedule Paul Graham wrote about the maker’s schedule in 2009 – basically that there are two types of schedules in this world (primarily?). On the other hand you have something PG calls the maker’s schedule – a schedule for those of us who produce stuff. This is why programmers are so annoyed when you distract them. Because of this huge mental investment, we simply can’t start working until we can expect a couple of hours without being distracted. The sleepy brain Bright computer screens Fin Fin
Comparison of e-book readers An e-book reader is a portable electronic device that is designed primarily for the purpose of reading e-books and periodicals. E-book readers are similar in form to a tablet computer, and usually refer to readers that use electronic paper, which means better readability of their screens especially in bright sunlight, and longer battery life. When disconnected from the web, an e-book reader's battery will last from weeks to months. A tablet computer typically has a faster screen capable of higher refresh rates which makes them more suitable for interaction. Any device that can display text on a screen can act as an e-book reader, but without the advantages of the e-paper technology. Commercially available devices sold by maker or designer[edit] Notes: Library DRM compatible – Can be used to borrow e-books from public libraries, i.e. the EPUB and/or PDF formats with digital-rights-management (DRM) are supported." Electronic-paper displays[edit] Different kinds of screens[edit] Changes[edit]
Beckstrom's law In economics, Beckstrom's law is a model or theorem formulated by Rod Beckstrom. It purports to answer "the decades old question of 'how valuable is a network'", and states in summary that "The value of a network equals the net value added to each user’s transactions conducted through that network, summed over all users." According to its creator, this law can be used to value any network be it social networks, electronic networks, support groups and even the Internet as a whole.[1] This new model values the network by looking from the edge of the network at all of the transactions conducted and the value added to each. It states that one way to contemplate the value the network adds to each transaction is to imagine the network being shut off and what the additional transactions costs or loss would be. As an explicit economic model[edit] where: = value of a network j to all users Vi,j = net present value of all transactions to user i with respect to network j, over any time period
Anatomy of Facebook Better, Cheaper French Cuisine Conductance (graph) in a graph is defined as: where the are the entries of the adjacency matrix for G, so that is the total number (or weight) of the edges incident with S. The conductance of the whole graph is the minimum conductance over all the possible cuts: Equivalently, conductance of a graph is defined as follows: For a d-regular graph, the conductance is equal to the isoperimetric number divided by d. In practical applications, one often considers the conductance only over a cut. The notion of conductance underpins the study of percolation in physics and other applied areas; thus, for example, the permeability of petroleum through porous rock can be modeled in terms of the conductance of a graph, with weights given by pore sizes. of the capacity of divided by the ergodic flow out of . for the conditional probability of leaving a set of nodes S given that we were in that set to begin with, the conductance is the minimal over sets that have a total stationary probability of at most 1/2. Béla Bollobás (1998).
Mozilla may make Flash click-to-play by default in future Firefox Firefox developers are considering making Web plugins like Adobe Flash an opt-in feature. Although there is still a long way to go before it’s ready for Firefox proper, switching to an opt-in, "click-to-play" approach for plugins could help make Firefox faster, more secure, and a bit easier on the laptop battery. A very early version of the "click-to-play" option for plugins is now available in the Firefox nightly channel. Once that’s installed you’ll need to type about:config in your URL bar and then search for and enable the plugins.click_to_play flag. Once that’s done, visit a page with Flash content and it won’t load until you click on it. While HTML5 reduces the need for Flash and other plugins, they’re still a big part of the Web today. Another popular solution is the click-to-play approach that Mozilla developers are considering. Whether or not the click-to-play approach that Mozilla is considering will ever become the default behavior for Firefox remains to be seen.
How to Edit PDF Files - Free Tools for Manipulating PDF Documents The PDF file format was originally created by Adobe in the early ’90s and it now the most popular format for exchanging all sorts of documents including presentations, CAD Drawings, invoices, government forms and other legal documents. There are several reasons why PDF file format is so popular. PDFs are generally more compact (smaller in size) than the source document and they preserve the original formatting. The content of a PDF file cannot be modified easily and you can prevent other users from printing or copying text from PDF documents. Also, you can open a PDF file on any computer or mobile device natively. While PDF Files are “read only” by default, there are workarounds that will let you modify any PDF document for free without requiring the source files or any of the commercial PDF editing tools like Adobe Acrobat. We are primarily focusing on tools that let you alter the actual contents of a PDF files. An Online PDF Editor for Basic Tasks Change Metadata of PDF Files
Reed's law Reed's law is the assertion of David P. Reed that the utility of large networks, particularly social networks, can scale exponentially with the size of the network. The reason for this is that the number of possible sub-groups of network participants is 2N − N − 1, where N is the number of participants. the number of participants, N, orthe number of possible pair connections, N(N − 1)/2 (which follows Metcalfe's law). so that even if the utility of groups available to be joined is very small on a peer-group basis, eventually the network effect of potential group membership can dominate the overall economics of the system. Derivation[edit] Quote[edit] From David P. "[E]ven Metcalfe's law understates the value created by a group-forming network [GFN] as it grows. Criticism[edit] Other analysts of network value functions, including Andrew Odlyzko and Eric S. See also[edit] References[edit] External links[edit]
Things You Should Never Do, Part I by Joel Spolsky Thursday, April 06, 2000 Netscape 6.0 is finally going into its first public beta. There never was a version 5.0. The last major release, version 4.0, was released almost three years ago. Three years is an awfully long time in the Internet world. It's a bit smarmy of me to criticize them for waiting so long between releases. Well, yes. They decided to rewrite the code from scratch. Netscape wasn't the first company to make this mistake. We're programmers. There's a subtle reason that programmers always want to throw away the code and start over. It’s harder to read code than to write it. This is why code reuse is so hard. As a corollary of this axiom, you can ask almost any programmer today about the code they are working on. Why is it a mess? "Well," they say, "look at this function. The idea that new code is better than old is patently absurd. Back to that two page function. Each of these bugs took weeks of real-world usage before they were found. Is there an alternative?
What's in a wine label? - Wine These days many enjoy buying wine with labels that feature animals: kangaroos, penguins, fish, lizards, and loons. These “critter labels” don’t just happen by accident — research shows that American wine consumers are 40 percent more likely to buy a wine with a cute animal on the label when compared to a straightforward label that gives the standard information: the name of the producer, the name of the grape, the name of the place where the vineyards are located, and the year in which the grapes were picked. But whether we choose our wines based on the cute factor or on the basic label facts, most wine labels give us minimal information; it’s up to the consumer to know about the vintage, the area where the grapes are grown, etc. Sometimes the back label of a wine is reserved for marketing the wine, and in the process of trying to hook the consumer with spinspiel, we learn a bit more about the origins of the wine and the philosophy of the producer. Let’s take a look. Filtration: None
Small-world network Small-world network exampleHubs are bigger than other nodes Average vertex degree = 1,917 Average shortest path length = 1.803. Clusterization coefficient = 0.522 Random graph Average vertex degree = 1,417 Average shortest path length = 2.109. In the context of a social network, this results in the small world phenomenon of strangers being linked by a mutual acquaintance. Properties of small-world networks[edit] This property is often analyzed by considering the fraction of nodes in the network that have a particular number of connections going into them (the degree distribution of the network). ) is defined as R. Examples of small-world networks[edit] Small-world properties are found in many real-world phenomena, including road maps, food chains, electric power grids, metabolite processing networks, networks of brain neurons, voter networks, telephone call graphs, and social influence networks. Examples of non-small-world networks[edit] Network robustness[edit] See also[edit] References[edit]
Expérience de Milgram Un article de Wikipédia, l'encyclopédie libre. Reconstitution de l'expérience de Milgram (extrait)[1] L’expérimentateur (E) amène le sujet (S) à infliger des chocs électriques à un autre participant, l’apprenant (A), qui est en fait un acteur. La majorité des participants continuent à infliger les chocs jusqu'au maximum prévu (450 V) en dépit des plaintes de l'acteur. L'expérience de Milgram est une expérience de psychologie réalisée entre 1960 et 1963 par le psychologue américain Stanley Milgram. Les résultats ont suscité beaucoup de commentaires dans l’opinion publique, mais la méthode utilisée a fait naître critiques et controverses chez les psychologues et les philosophes des sciences. Déroulement de l'expérience[modifier | modifier le code] Fac-similé de l'annonce L'objectif réel de l'expérience est de mesurer le niveau d'obéissance à un ordre même contraire à la morale de celui qui l'exécute. La majorité des variantes de l'expérience a eu lieu dans les locaux de l'université Yale.
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