dreamers with empty hands …

November 12, 2011


daily snapshot | November 5 2011

November 5, 2011
  • The Clientele on the radio .. beauty will save the world 🙂
  • MurmurHash for fun & profit at org.apache.mahout.math.MurmurHash3
  • Efficient vectorization as key to common expression of arbitrary learning tasks. General-purpose distributed matrix computation? (Octave -> Hama compilation etc.)
  • Nonlinearity hypotheses are inherent in complex sensory data (computer vision, machine listening problems …) What is the rationale for assuming nonlinearity in social/economic data ?
  • Does active interaction with the data “train” the receptor to recognize nonlinearity ? Can this be the rationale for difference in cognitive processes when listening to song vs making decisions on the purchase of the product ?

VC Research notes #01

July 7, 2011
  •  “IPOs, trade sales and liquidations: modelling venture capital exits using survival analysis” , Pierre Giot, Armin Schwienbacher (2005) – excellent treatise of US VC funds exit options ( Time-To-{IPO, Trade Sale, Liquidation} ) using survival analysis.
  • “The quantitative economics of Venture Capital” , Robert E. Hall, Susan E. Woodward (2007)
Research Questions:
  • Supply and demand equilibrium dynamics in venture capital markets. The case of Angellist.
  • What influences VC investitors to invest outside of their “preferred habitat” ?
  • VC risk diversification and impact to geographical distribution of investments
  • Exit preferences of VC’s in startup companies and it’s impact to company policy in light of financial results
  • Industry survey of factors influencing early-stage Angel and VC investments
  • Risk and Reward preferences of Angel vs Venture Capital investors and it’s contributions to company success
  • Are Angels informed gamblers and VC’s lemmings ?
  • Portfolio Management practice differences between Angel and Venture Capital investors ?

On Relevance of Information …

June 5, 2011

“I don’t deny it,”, answered Swann in some bewilderment. “The fault I find with our journalism is that it forces us to take an interest in some fresh triviality or other every day, whereas only three or four books in a lifetime give us anything that is of real importance. Suppose that, every morning, when we tore the wrapper off our paper with fevered hands, a transmutation were to take place, and we were to find inside it-oh! I don’t know; shall we say Pascal’s Pensees?”. He articulated the title with an ironic emphasis so as not to appear pedantic. “And then, in the gilt and tooled volumes which we open once in ten years,” he went on, shewing that contempt for the things of this world which some men of the world like to affect, “we should read that the Queen of the Hellens had arrived at Cannes, or that the Princesse de Leon had given a fancy dress ball. In that way we should arrive at the right proportion between ‘information’ and ‘publicity.'”

(À la recherche du temps perdu, Marcel Proust, 1913)

dotproduct #01

June 5, 2011

in-flight experimentations | ipad-handcrafted

:notes | may 15

May 15, 2011

continuations on & on …

May 8, 2011

random notes on continuation-style programming:

  • The idea of continuations makes a lot of sense when building state-machine-encodable applications. This is particularly interesting nowadays when developing “modern” stateful Javascript applications.
  • (of course, let’s not forget that with continuations being just a functional goto’s 🙂 – Dijkstra would probably have a few words to say on the topic.)
  • “… and times being what they are …”
  • Anyhow – the big question here is the one of RESTful continuations.
  • Assuming a naive implementation – this assumes introducing state on the service side, which is contrary to the REST concepts.
  • Of course – this is not necessary so, as state can be transfered to client and posted/updated with every request, etc …
  • (good writing on the subject : Web Programming with Continuations, William E. Byrd (2002) )
  • Another semi-related one: Automatically Restructuring Programs for the Web
  • Everyone loves Apache Cocoon‘s support for continuation-style …
  • General concern is along the traditional lines of web services and dealing with async callbacks, usage of closures, etc..
  • Remembering Appel’s seminal paper : Continuation-Passing, Closure-Passing Style.
  • Finally – an excellent presentation on the subject : Continuations continued: the REST of the computation

daily snapshot | 25 May 2011

April 25, 2011

a quick discourse on dependency injection

April 25, 2011
  • +1 : less boilerplate code for component initialization
  • -1 : boilerplate code can be reduced by moving initialization to library + app-specific conf
  • +1 : DI might provide standardized way to do so – valuable especially for common components such as db
  • +1 : Easy to provide mock implementations -> supporting testing (separate setup for conf)
  • -1 : More difficult to debug / trace issues
  • -1 : As flexibility is added to the interaction with injected object – the complexity of debugging increases
  • +1 : But components can be tested in isolation and covered with tests
  • -1 : Though this definitely introduces longer development time. Great on off-the shelf components but challenge for one-off custom code
  • -1 : Promotes IDE dependency for developers (no more emacs)
  • ….
  • summary: A priori usage of dependency injection without proper justification can come at the price

daily snapshot | 22 april 2011

April 22, 2011

  • “Sed is the ultimate stream editor. If that sounds strange, picture a stream flowing through a pipe. Okay, you can’t see a stream if it’s inside a pipe. That’s what I get for attempting a flowing analogy. You want literature, read James Joyce.” – http://www.grymoire.com/Unix/Sed.html
  • Minimal usable syntax for describing Turing-complete set of operations on arbitrary text streams ?
  • Java boxing, heap pollution and long-term worst-case app performance. Unknown pleasures.
  • Extract unique values from “number 424242“-style patterns in newline-delimited file :  cat file | grep number | sed ‘s/.* number \([0-9]*\) .*/\1/’ | sort | uniq -c