Nanos gigantium humeris insidentes!

Bayesian inference

  • October 12, 2013 5:21 pm
Statistical inference is the process of drawing conclusions from data that are subject to random variation.
Bayesian inference
Bayesian inference is a method of inference in which Bayes’ rule is used to update the probability estimate for a hypothesis as additional evidence is acquired. Bayesian updating is an important technique throughout statistics, and especially in mathematical statistics.

Dependency tree

  • July 29, 2013 9:40 pm

I should try applying dependency tree to the KiwiPredator.

KiwiPredator Architecture

  • July 16, 2013 12:05 am

Feel free to check out my repo at





Parser is the component that converts sentence into a parser tree. Which is done by Stanford Parser. 


Extractor is the component that extract subject, predict and object from a sentence. It contains two main parts — a markup language called tree-based regular expression language (TREL), its interpreter and a tregex engine which perform regular expression on a parser tree.

TREL has two characteristics.

  • Markup Language
  • Inheritance

There are three main types of ERML. Splitting, Pruning and Replacing.

  • Splitting: Mainly used for splitting one tree into several subtrees.
  • Pruning: Mainly used for pruning uninterested parts.
  • Replacing: Mainly used for replacing pronoun, tense and number type.


Evaluator reviews the hypothesis and either takes it as a new item of knowledge or discard it. In either case, it will send feedback to the TREL. 


  • February 19, 2013 8:37 pm

I am switching to the tree-based regular expression.

The basic idea is using Tregex to prune the parser tree to get the essential of a sentence.

Reasoning with Graph

  • January 11, 2013 12:07 pm

Key Value Store options

  • January 9, 2013 2:58 pm
  • BabuDB

    BabuDB is an embedded non-relational database system. Its lean and simple design allows it to persistently store large amounts of key-value pairs without the overhead and complexity of similar approaches such as BerkeleyDB.

    License: New BSD license, Language: Java


    JDBM2 provides HashMap and TreeMap which are backed by disk storage.

    License: Apache License 2.0, Language: Java

    Banana DB

    Banana DB is a self-contained key/value pair database implemented in Java.

    License: Apache License 2.0, Language: Java

    I’ve tried BabuDB and JDBM2 and they work fine. BabuDB is a little bit more difficult to set up, but potentially delivers higher performance than JDBM2.


  • January 5, 2013 7:40 pm

Survey of Graph Database Models

  • January 5, 2013 5:54 pm


Computer Science Department, Universidad de Chile



a graph db-model is characterized by:

The data and/or the schema are represented by graphs, or by data structures generalizing the notion of graph (hypergraphs or hypernodes).

  •  The approach is to model the database directly and entirely as a graph [G¨uting 1994].
  • A graph db-model is one whose single underlying data structure is a labeled directed graph; the database consists of a single digraph [Levene and Loizou 1995].
  • A database schema in this model is a directed graph, where leaves represent data and internal nodes represent connections between the data [Kuper and Vardi 1984].
  • Directed labeled graphs are used as the formalism to specify and represent database schemas, instances, and rules [Paredaens et al. 1995].
  • In this model, a database is described in terms of a labeled directed graph called schema graph [Kunii 1987].
  • A graph db-model formalizes the representation of the data structures stored in the databases as a graph [Graves et al. 1995a].
  • The schema as well as the instance of an object database is represented by a graph. The nodes of the instance represent the objects of the database [Gyssens et al. 1990].
  • Database instances and database schemas are described by certain types of labeled graphs [Hidders 2002].
  • The model for data is organized as graphs [Amann and Scholl 1992]. Labeled graphs are used to represent schemas and instances [Hidders and Paredaens 1993].

Data manipulation is expressed by graph transformations [Gyssens et al. 1990], or by operations whose main primitives address directly typical features of graphs, like paths, neighborhoods, subgraphs, graph patterns, connectivity, and statistics about graphs (diameter, centrality, etc.)


A.12 Related Data Models

Survey of Open Source Search Engine

  • January 4, 2013 2:47 pm

VIM command

  • December 26, 2012 4:00 pm