23. 7.

Tablet z Číny

Asi niekedy v marci (2012) sa objavil SoC Allwinner A10, ktorý sa razom stal veľmi populárnym. Malo to viacero dôvodov, ten základný je úžasný pomer cena/výkon – SoC za $7. A začala sa výroba lacných tabletov s podporou najnovšej verzie Androida (zariadenia teraz okolo $105/86€, okresaná verzia A13 okolo $75/62€).

Ďalším dôležitým bodom je aj podpora bežného Linuxu – výhľadovo aj podpora OpenGL a akcelerovaného dekódovania videa, a taktiež je “unbrickable” (pomocou USB, údajne aj nejakej bootovateľnej SD karty, je možné nahrať tam funkčný systém).

Okrem Android zariadení sa začali rojiť aj iné open hardware Linux/Android projekty (napr. rôzne HTPC), ktoré na tomto SoC stavajú. Je to zaujímavý a celkom výkonný kus hardvéru, 1.5GHz ARM Cortex A8 s Mali-400 GPU/VPU (podpora dekódovania až 2160p videí).

Som rád, že som sa o tomto nedozvedel v marci, určite by som neodolal, hoci som na to vtedy nemal dostatok času a taktiež bol aj problém s dodávkami zariadení, šlo to ako teplé rožky. Teraz už je dobre.

Stručná špecifikácia:

  • jednojadrový ARM Cortex A8, až 1.5 GHz
  • Mali 400 GPU + CedarX VPU (2160p HW video decoding)
  • 1G DDR3 RAM
  • 16G internal memory
  • TF (Micro SD) slot
  • mini USB (OTG support)
  • mini HDMI output
  • 7” 1024×600 capacitive screen with multitouch (nie je to IPS)
  • 1.3Mpix front camera
  • WiFi 802.11 b/g/n
  • rotation sensor/accelerometer – nejak divne funguje, hru by som s tým nehral a autorotate som vypol

Takže zlákala ma rozprávková cena, aj keď som vopred vedel, že pre tablet budem musieť hľadať využitie. No nikdy som nemal Android ani touchscreen. Bolo na čase sa s týmto zázrakom zoznámiť. Teraz som presvedčený, že ho na mobil ani nechcem. Jeden dôvod je, že touchová klávesnica je celkom peklo aj na tých 7 palcoch. A ďalší je ten, že moja Nokia E52 má aj po dvoch rokoch stále priemer vyše 10 dní na jedno nabitie.

Teraz píšem tento blog, už som mal niekoľko dní možnosť povŕtať sa v tablete a zhodnotiť situáciu. V prvom rade som od toho neočakával veľa, nie nadarmo sa to volá toilet computer, no premohla ma tá úžasná cena, kvôli ktorej ani veľmi neľutujem – ostatne vždy z toho môžem spraviť (takmer) plnohodnotné HTPC. Pracuje sa aj na XBMC pre Android, ktorý už mám odskúšaný, chýba mu len podpora hardvérového dekódovania videa.

Tabletu samotnému nemám veľmi čo vytknúť, funguje pekne. Originálny firmware je rootnutý, takže najvoľnejšia Android platforma sú asi ozaj lacné čínske tablety.

Na druhú stranu to veľmi neodporúčam ľuďom, ktorí tomu nerozumejú, musel som si tam nahrať ClockworkMod a cez neho nainštalovať Google Apps – čím som získal napríklad Google Talk aplikáciu, ale určite aj nejaké drobnosti, ktoré viac prepoja Android s Google účtom.

Najväčší problém bol ale v tom, že Google Play Store identifikoval niektoré aplikácie ako nekompatibilné so zariadením. Toto ale nie je problém tabletu, ale problém Google. Google si za toto zaslúži nakopať. Ak máte odniekiaľ APK balík, ten sa nainštaluje, to iba Play Store odmieta tieto aplikácie sprístupniť. Sú to napríklad Facebook for Android alebo Angry Birds. Väčšina má problém, pretože tablet nesprístupňuje službu Location (alebo niečo také, tých Location služieb tam je viacero) a niektoré pretože tablet nemá Bluetooth. Toto sa dá vyriešiť nahradením a pridaním niektorých XML súborov v /system/etc/permissions/ (stačí ako root remountnúť /system a skopírovať napr. z SD karty). Vo wiki článku Cheap Chinese Android 4.0 tablet mám nejaké odkazy na takéto XML súbory.

Vyskytol sa aj problém v Skype, kde bolo nutné použiť staršiu verziu, pretože v novších bolo odosielané video nejaké ružové. Na to by som sám neprišiel, Skype som doteraz nikdy nepoužil, ale našiel som to niekde na fórach aj s odkazom na dobrú verziu. Google Talk vykonáva aj video hovor s GMailom bez problémov (Pidgin s podporou Voice and Video padá skôr než stihne oznámiť prichádzajúci hovor, ale možno mám iba starú verziu). Mimochodom, 1.3Mpix kamera na toto samozrejme postačuje, ale nejaké rozumné fotky to samozrejme nedáva.

Takže celkom som potešený s kvalitou. Dúfam, že sa čoskoro objaví aj Android 4.1 od výrobcu, Google Now (konkurenciu Siri) si určite chcem vyskúšať. A možno sa pošťastí s CyanogenMod 10.

Na záver ešte pridám zoznam potenciálne užitočných využití (väčšina pomocou špeciálnych aplikácií):

  • Google Reader – zatiaľ moje jediné seriózne využitie,
  • Google Calendar,
  • predpoveď počasia,
  • Facebook a Google+,
  • v budúcnosti XBMC HTPC – asi by to potrebovalo pripojiť USB disk pomocou OTG kábla,
  • čítanie stiahnutých offline článkov a možno aj kníh,
  • prehrávač hudby (keď náhodou ešte nevlastníte mobil) a filmov na cesty,
  • browsovanie (tethering z mobilu alebo 3G USB dongle, keď nie je WiFi),
  • čítanie mailov (GMail aj IMAP),
  • Reddit (cez browser),
  • Skype / Google Talk hovory,
  • IRC a iné chaty/messengery – nepohodlné písanie,
  • Google Maps – obmedzené využitie bez GPS (USB dongle?), ale dá sa stiahnuť časť mapy,
  • Geocaching – obmedzené využitie bez GPS,
  • IMHD aplikácia (BA/KE),
  • možno písanie poznámok alebo anotácie PDF (nemám stylus, no veľa by som od toho neočakával),
  • hry.

A aplikácie, ktoré sa mi páčili:

  • AdAway – na odstránenie otravných reklám,
  • FancyWidgets – počasie (Google News&Weather/GenieWidget.apk prestal fungovať),
  • Winamp – na prehrávanie hudby a shoutcast rádií,
  • Jazz Internet Radio – jazzové streamy,
  • MX Player – na prehrávanie videí,
  • Droid MPD – na ovládanie MPD (prehrávač hudby),
  • Pocket – na čítanie offline článkov,
  • Cool Reader alebo FBReader – na čítanie kníh,
  • Terminal IDE – sprístupňuje niektoré zaujímavé aplikácie (ssh, htop, powertop),
  • c:geo – na prezeranie mapy s geocache,
  • Dropbox či Google Drive sa tiež môžu zísť,
  • Adobe Reader,
  • Angry Birds – na zabitie času,
  • na browsovanie snáď radšej akýkoľvek iný browser (Opera Mobile, Firefox, niekde som videl chválu na Dolphin).

Už sa mi to po sebe nechce čítať, snáď to dáva zmysel. Zhrnutie: tablet je blbosť, ale dá sa už kúpiť ako hračka na gaučové konzumovanie (web 2.0) obsahu za rozumnú cenu – prípadne nahradí aj HTPC. A pro-tip na záver: obrazovka nie je žiaden Gorilla/Corning glass, takže ked to padne na zem alebo ho rozpučíte, už to ako tablet nepoužijete (náhradný touchscreen sa predáva za nejakých $40).

17. 6.

Thinking, Fast and Slow (Daniel Kahneman)

Knihu Thinking, Fast and Slow odporúčam každému, kto je schopný čítať v angličtine. Viac k tomu ani nemám čo povedať, sú tam zhrnuté myšlienky a objavy o vnímaní a myslení človeka, ktoré sa vzťahujú na každého. Je tam aj spomenutých viacero postupov alebo tipov ako sa intuitívnym chybám v myslení vyhnúť.

Pre svoju potrebu a pre čitateľov planet.opensoft.sk nižšie prikladám nejaké citácie z knihy.

 The busy and depleted System 2:
 The list of indications of depletion is also highly diverse:
 - deviating from one's diet
 - overspending on impulsive purchases
 - reacting aggressively to provocation
 - persisting less time in a handgrip task
 - performing poorly in cognitive tasks and logical decision making
 The ease with which they are satisfied enough to stop thinking is
 rather troubling. "Lazy" is a harsh judgment about the
 self-monitoring of these young people and their System 2, but it
 does not seem to be unfair. Those who avoid the sin of intellectual
 sloth could be called "engaged." They are more alert, more
 intellectually active, less willing to be satisfied with
 superficially attractive answers, more skeptical about their
 intuitions. The psychologist Keith Stanovich would call them more
 rational.
 A happy mood loosens the control of System 2 over performance: when
 in a good mood, people become more intuitive and more creative but
 also less vigilant and more prone to logical errors. Here again, as
 in the mere exposure effect, the connection makes biological
 sense. A good mood is a signal that things are generally going
 well, the environment is safe, and it is all right to let one's
 guard down. A bad mood indicates that things are not going very
 well, there may be a threat, and vigilance is required.
 The moral is significant: when System 2 is otherwise engaged, we
 will believe almost anything. System 1 is gullible and biased to
 believe, System 2 is in charge of doubting and unbelieving, but
 System 2 is sometimes busy, and often lazy. Indeed, there is
 evidence that people are more likely to be influenced by empty
 persuasive messages, such as commercials, when they are tired and
 depleted.
 A simple rule can help: before an issue is discussed, all members
 of the committee should be asked to write a very brief summary of
 their position. This procedure makes good use of the value of the
 diversity of knowledge and opinion in the group. The standard
 practice of open discussion gives too much weight to the opinions
 of those who speak early and assertively, causing others to line up
 behind them.
 Evaluating people as attractive or not is a basic assessment. You
 do that automatically whether or not you want to, and it influences
 you.
 The present state of mind looms very large when people evaluate
 their happiness.
 I began this chapter with the example of cancer incidence across
 the United States. The example appears in a book intended for
 statistics teachers, but I learned about it from an amusing article
 by the two statisticians I quoted earlier, Howard Wainer and Harris
 Zwerling. Their essay focused on a large investment, some $1.7
 billion, which the Gates Foundation made to follow up intriguing
 findings on the characteristics of the most successful
 schools. Many researchers have sought the secret of successful
 education by identifying the most successful schools in the hope of
 discovering what distinguishes them from others. One of the
 conclusions of this research is that the most successful schools,
 on average, are small. In a survey of 1,662 schools in
 Pennsylvania, for instance, 6 of the top 50 were small, which is an
 overrepresentation by a factor of 4. These data encouraged the
 Gates Foundation to make a substantial investment in the creation
 of small schools, sometimes by splitting large schools into smaller
 units. At least half a dozen other prominent institutions, such as
 the Annenberg Foundation and the Pew Charitable Trust, joined the
 effort, as did the U.S. Department of Education's Smaller Learning
 Communities Program.
 
 This probably makes intuitive sense to you. It is easy to construct
 a causal story that explains how small schools are able to provide
 superior education and thus produce high-achieving scholars by
 giving them more personal attention and encouragement than they
 could get in larger schools. Unfortunately, the causal analysis is
 pointless because the facts are wrong. If the statisticians who
 reported to the Gates Foundation had asked about the
 characteristics of the worst schools, they would have found that
 bad schools also tend to be smaller than average. The truth is that
 small schools are not better on average; they are simply more
 variable. If anything, say Wainer and Zwerling, large schools tend
 to produce better results, especially in higher grades where a
 variety of curricular options is valuable.
 One of the best-known studies of availability suggests that
 awareness of our own biases can contribute to peace in marriages,
 and probably in other joint projects. In a famous study, spouses
 were asked, "How large was your personal contribution to keeping
 the place tidy, in percentages?" They also answered similar
 questions about "taking out the garbage," initiating social
 engagements," etc. Would the self-estimated contributions add up to
 100%, or more, or less? As expected, the self-assessed
 contributions added up to more than 100%. The explanation is a
 simple availability bias: both spouses remember their own
 individual efforts and contributions much more clearly than those
 of the other, and the difference in availability leads to a
 difference in judged frequency. The bias is not necessarily
 self-serving: spouses also overestimated their contribution to
 causing quarrels, although to a smaller extent than their
 contributions to more desirable outcomes. The same bias contributes
 to the common observation that many members of a collaborative team
 feel they have done more than their share and also feel that the
 others are not adequately grateful for their individual
 contributions.
 As you already know, frowning normally accompanies cognitive strain
 and the effect is symmetric: when people are instructed to frown
 while doing a task, they actually try harder and experience greater
 cognitive strain. The researchers anticipated that the frowners
 would have more difficulty retrieving examples of assertive
 behavior and would therefore rate themselves as relatively lacking
 in assertiveness. And so it was.
 
 ...
 
 For example, people:
 - believe that they use their bicycles less often after recalling
   many rather than few instances
 - are less confident in a choice when they are asked to produce
   more arguments to support it
 - are less confident that an event was avoidable after listing more
   ways it could have been avoided
 - are less impressed by a car after listing many of its advantages
 Highly intelligent women tend to marry men who are less intelligent
 than they are. :)
 A general limitation of the human mind is its imperfect ability to
 reconstruct past states of knowledge, or beliefs that have
 changed. Once you adopt a new view of the world (or of any part of
 it), you immediately lose much of your ability to recall what you
 used to believe before your mind changed.
 Although hindsight and the outcome bias generally foster risk
 aversion, they also bring undeserved rewards to irresponsible risk
 seekers, such as a general or an entrepreneur who took a crazy
 gamble and won. Leaders who have been lucky are never punished for
 having taken too much risk. Instead, they are believed to have had
 the flair and foresight to anticipate success, and the sensible
 people who doubted them are seen in hindsight as mediocre, timid,
 and weak. A few lucky gambles can crown a reckless leader with a
 halo of prescience and boldness.
 We should have quit that day. None of us was willing to invest six
 more years of work in a project with a 40% chance of
 failure. Although we must have sensed that persevering was not
 reasonable, the warning did not provide an immediately compelling
 reason to quit. After a few minutes of desultory debate, we
 gathered ourselves together and carried on as if nothing had
 happened. The book was eventually completed eight(!) years
 later. By that time I was no longer living in Israel and had long
 since ceased to be part of the team, which completed the task after
 many unpredictable vicissitudes. The initial enthusiasm for the
 idea in the Ministry of Education had waned by the time the text
 was delivered and it was never used.
 Optimism is normal, but some fortunate people are more optimistic
 than the rest of us. If you are genetically endowed with an
 optimistic bias, you hardly need to be told that you are a lucky
 person--you already feel fortunate. An optimistic attitude is
 largely inherited, and it is part of a general disposition for
 well-being, which may also include a preference for seeing the
 bright side of everything. If you were allowed one wish for your
 child, seriously consider wishing him or her optimism. Optimists
 are normally cheerful and happy, and therefore popular; they are
 resilient in adapting to failures and hardships, their chances of
 clinical depression are reduced, their immune system is stronger,
 they take better care of their health, they feel healthier than
 others and are in fact likely to live longer. A study of people who
 exaggerate their expected life span beyond actuarial predictions
 showed that they work longer hours, are more optimistic about their
 future income, are more likely to remarry after divorce (the
 classic "triumph of hope over experience"), and are more prone to
 bet on individual stocks. Of course, the blessings of optimism are
 offered only to individuals who are only mildly biased and who are
 able to "accentuate the positive" without losing track of reality.
 More generally, the financial benefits of self-employment are
 mediocre: given the same qualifications, people achieve higher
 average returns by selling their skills to employers than by
 setting out on their own. The evidence suggests that optimism is
 widespread, stubborn, and costly.
 Entrepreneurs who have failed are sustained in their confidence by
 the probably mistaken belief that they have learned a great deal
 from the experience.
 average outcome is a loss: A form of competition neglect has also
 been observed in the time of day at which sellers on eBay choose to
 end their auctions. The easy question is: At what time is the total
 number of bidders the highest? Answer: around 7:00 p.m. EST. The
 question sellers should answer is harder: Considering how many
 other sellers end their auctions during peak hours, at what time
 will there be the most bidders looking at my auction? ...
 They cite John Gottman, the well-known expert in marital relations,
 who observed that the long-term success of a relationship depends
 far more on avoiding the negative than on seeking the
 positive. Gottman estimated that a stable relationship requires
 that good interactions outnumber bad interactions by at least 5
 to 1. Other asymmetries in the social domain are even more
 striking. We all know that a friendship that may take years to
 develop can be ruined by a single action.
 Remarkably, altruistic punishment is accompanied by increased
 activity in the "pleasure centers" of the brain. It appears that
 maintaining the social order and the rules of fairness in this
 fashion is its own reward. Altruistic punishment could well be the
 glue that holds societies together.
 A comment I heard from a member of the audience after a lecture
 illustrates the difficulty of distinguishing memories from
 experiences. He told of listening raptly to a long symphony on a
 disc that was scratched near the end, producing a shocking sound,
 and he reported that the bad ending "ruined the whole experience."
 But the experience was not actually ruined, only the memory of
 it. The experiencing self had had an experience that was almost
 entirely good, and the bad end could not undo it, because it had
 already happened. My questioner had assigned the entire episode a
 failing grade because it had ended very badly, but that grade
 effectively ignored 40 minutes of musical bliss. Does the actual
 experience count for nothing?
 
 Confusing experience with the memory of it is a compelling
 cognitive illusion--and it is the substitution that makes us
 believe a past experience can be ruined. The experiencing self does
 not have a voice. The remembering self is sometimes wrong, but it
 is the one that keeps score and governs what we learn from living,
 and it is the one that makes decisions. What we learn from the past
 is to maximize the qualities of our future memories, not
 necessarily of our future experience. This is the tyranny of the
 remembering self.
 While I have not formally studied the reactions to this scenario,
 my impression from discussing it with people is that the
 elimination of memories greatly reduces the value of the
 experience. In some cases, people treat themselves as they would
 treat another amnesic, choosing to maximize overall pleasure by
 returning to a place where they have been happy in the
 past. However, some people say that they would not bother to go at
 all, revealing that they care only about their remembering self,
 and care less about their amnesic experiencing self than about an
 amnesic stranger. Many point out that they would not send either
 themselves or another amnesic to climb mountains or trek through
 the jungle--because these experiences are mostly painful in real
 time and gain value from the expectation that both the pain and the
 joy of reaching the goal will be memorable.
 
 "You seem to be devoting your entire vacation to the construction
 of memories. Perhaps you should put away the camera and enjoy the
 moment, even if it is not very memorable?"
 
 moja asociácia: http://www.chucklorre.com/index-2hm.php?p=312
 The social norm against stereotyping, including the opposition to
 profiling, has been highly beneficial in creating a more civilized
 and more equal society. It is useful to remember, however, that
 neglecting valid stereotypes inevitably results in suboptimal
 judgments. Resistance to stereotyping is a laudable moral position,
 but the simplistic idea that the resistance is costless is
 wrong. The costs are worth paying to achieve a better society, but
 denying that the costs exist, while satisfying to the soul and
 politically correct, is not scientifically defensible. Reliance on
 the affect heuristic is common in politically charged
 arguments. The positions we favor have no cost and those we oppose
 have no benefits. We should be able to do better.
weblog.txt · Last modified: 2010/08/03 08:21 (external edit)