quarta-feira, 20 de março de 2013

API de otimização com Python

Hoje eu descobri o projeto puLP: https://code.google.com/p/pulp-or/ e vi que se trata de um solucionador para problemas de otimização linear com suporte para a lingaugem Python.

O puLP por sua vez é baseado no projeto GLPK: http://www.gnu.org/software/glpk/glpk.html que implementa os algoritmos de otimização linear.

O objetivo da otimização linear é obter valores que maximizem ou minimizem uma determinada variável que é linearmente dependente de um conjunto de variáveis independentes, mais informações http://pt.wikipedia.org/wiki/Otimiza%C3%A7%C3%A3o e http://pt.wikipedia.org/wiki/Programa%C3%A7%C3%A3o_linear

Assim, da próxima vez que você precisar encontrar a melhor solução para um problema já equacionado e não sabe como proceder, procure um software aberto que te ajude com a matemática por trás da otimização.

terça-feira, 12 de março de 2013

Olhar de gafanhoto evita que você bata o carro

Olhar de gafanhoto evita que você bata o carro: Os gafanhotos possuem uma forma de processamento das informações visuais extremamente rápida e incorporada em sua própria biologia.

Como muitas das principais inovações em tecnologia de sensoriamento e navegação, mais uma vez a natureza tem mostrado uma solução mais adequada que a abordagem tradicional.

Quando for possível modelar o sistema visual, e/ou de navegação, de animais mais complexos, como aves e mamíferos, talvez seja possível o desenvolvimento de sistemas com muito mais autonomia do que o que existe atualmente.

sexta-feira, 8 de março de 2013

Softwares gratuitos de análise estatística

Hoje vi este site: http://www.analyticbridge.com/forum/topics/list-of-free-statistical e achei que seria muito interessante difundir todo o trabalho desenvolvido para a elaboração de softwares estatísticos gratuitos.

Segue a lista de softwares em ordem alfabética.

ADaMsoft - Data mining, data management and reporting. Has web based features.
Ade4 - It contains Data Analysis functions to analyse Ecological and Environmental data in the framework of Euclidean Exploratory methods, hence the name ade4.
ADePT - Developed to automate and standardize the production of analytical reports.
ADMB - Non-linear statistical modelling.
AM  General stats package.
AnSWR - A software system for coordinating and conducting large-scale, team-based analysis projects that integrate qualitative and quantitative techniques.
Apophenia - General stats package but with more flexibility to be creative in model building.
Arc - Applied regression including computing and graphics.
Assistat - General stats package.

Bayesian Filtering Library - Bayesian software for use in advanced machine and robot control.
BiNGO - Bioinformatics software. Biological Network Gene Ontology.
BioEstat - Ecological statistics program (only available in Portuguese).
Biogeme - Stands for: Bierlaire's Optimization Toolbox for GEV (Generalized Extreme Value) Model Estimation.
Biomapper - A GIS-toolkit to model ecological niche and habitat suitability.
BKD - Bayesian Knowledge Discoverer
BlockTreat - A general frequentist Monte Carlo program for block and treatment tests, tests with matching, k-sample tests, and tests for independence.
BrightStat - General stats package.
BV4.1 - A procedure for the decomposition and seasonal adjustment of monthly and quarterly economic series. Used by the German Federal Statistical Office.

Calcugator - Calculator, plotting engine, and programming environment.
Caleydo - Bioinformatics data visualisation software.
CCOUNT - Designed for market research purposes, including: data cleaning, manipulation, cross tabulation and data analysis. Similar to SPSS.
CDC EZ-Text - Developed to assist researchers create, manage, and analyze semi-structured qualitative databases.
Chronux - Developed for the analysis of neural data.
Conc - Text concordance program.
Concorder - Text concordance program. Allows you to take given texts and find out the frequency of words.
Correlate -
CSPro - Census and Survey Processing System (CSPro) is a questionnaire-oriented statistical package for Windows.
Cytoscape - Bioinformatics software platform for visualizing molecular interaction networks and integrating these interactions with gene expression profiles and other state data.

DAP - Alternative to SAS.
Dataplot - General stats package. Designed for science and engineering.
DAVID - Bioinformatics software. Database for Annotation, Visualization and Integrated Discovery.
dChip - Bioinformatics software. dChip Software: Analysis and visualization of gene expression and SNP microarrays
Demetra - Time series package.
Dia - Diagram drawing program. Allows the drawing of entity relationship diagrams, UML diagrams, flowcharts, network diagrams, and many others.
Draco - Econometrics package with spreadsheets.

EASE - Bioinformatics software. Expression Analysis Systematic Explorer.
EasyReg Int. - Econometrics package.
EasySample - Simple sampling program.
EDGAR - Experimental design programs.
ELKI - Environment for developing KDD-applications supported by index-structures. Compares data mining algorithms.
EMMIX - Fortran software to fit mixture models.
Epi Info - Designed for epidemiologists and other public health and medical professionals.
Epidata - Epidemiology package.
EqPlot - Equation graph plotter.
ErmineJ - Bioinformatics software. Performs analyses of gene sets in expression microarray data or other genome-wide data that results in rankings of genes.
ESA - Event Structure Analysis (ESA) is an on-line Java program that helps you analyze sequential events.
ESS - Emacs Speaks Statistics. Add-on package for emacs text editors.
Esta+ - General (and simple) stats package.
Euler - Similar to Matlab.
EVE - Embedded Vector Editor. Vector graphics program.
Excellent Analytics - Excel plug-in that lets you import web analytics data from Google Analytics into a spreadsheet.
EzANOVA - Simple ANOVA program.

Factor - Simple factor analysis program.
Firebird - Relational database management system (RDBMS).
Fityk - Nonlinear least squares curve fitting.
Freemat - Similar to Matlab and IDL.

G Power - Power and sample size calculator.
G7 - Econometrics package. Allows the building and useage of data banks.
GATE - Text mining program. General Architecture for Text Engineering.
Gemma - Bioinformatics software. Database and software system for the meta-analysis of gene expression data.
GEMS - Bioinformatics software (online forms). Gene Expression Module Sampler.
GenePattern -Bioinformatics software. Genomic analysis platform that provides access to more than 125 tools for gene expression analysis, proteomics, SNP analysis and more.
GenMAPP - Bioinformatics software. Designed to visualize gene expression and other genomic data on maps representing biological pathways and groupings of genes.
GeoDa - Geospatial analysis and computation.
GGobi - Data visualisation.
Gist - Bioinformatics software. Contains software tools for support vector machine classification and for kernel principal components analysis.
Gnumeric - Spreadsheet program.
Gnuplot - Command driven graphing program.
GoMiner - Bioinformatics software. A tool for biological interpretation of 'omic' data, including data from gene expression microarrays.
Gostat - Bioinformatics software (online forms). Find statistically overrepresented Gene-Ontology (GO) terms within a group of genes.
Gretl - Stands for Gnu regression, econometrics and time-series library. Alternative to EViews. REVIEWED!!!
Grocer - An econometric toolbox for Scilab.
GUIDE - Multi-purpose machine learning algorithm for constructing classification and regression trees.

HLM - Hierarchical linear and nonlinear modelling.

IHMC CmapTools - Concept mapping program.
Instats - General stats package.
Interactive Statistical Unit -
Inverse Symbolic Calculator - An online form where the output is a list of possible sources for the number you enter (such as simple equations or well known constants).
IRRIStat - General stats package. Designed for analysis of agricultural field trials data.
IVEware - Imputation and Variance Estimation.

JAGS - Stands for just another Gibbs sampler. Bayesian hierarchical models using Markov Chain Monte Carlo (MCMC).
jHepWork - Mathematics and statistics package.
JMulTi - Time series and econometrics package.

Kyplot - Graphs program.

Lisp-stat - General stats package with emphasis on graphics.
LISREL - Originally limited to structural equation modelling (SEM) but now has other functions.

MacAnova - General stats package.
MacSHAPA - Macintosh-based software environment that supports observational data analysis, including the analysis of video.
Matrixer - Econometrics package.
Matrix2png - Bioinformatics software. A simple program for making visualizations of microarray data and many other data types.
Matvec - Current capabilities range from matrix and vector manipulation to the analysis of linear and generalized linear mixed models.
Maxima - A computer algebra system. Mathematics program.
MicroConcord - Text concordance program.
MicrOsiris - Statistical and data management package.
Ministep - Constructs Rasch measures from simple rectangular data sets.
MINUIT - Physics analysis tool for function minimization.
Mondrian - Data visualisation.
MorePower - Statistical power calculator for hypothesis tests.
Mx - Matrix algebra interpreter and numerical optimizer for structural equation modelling and other types of statistical modelling of data.
MYSTAT - Free SYSTAT version for students.

NLTK - Text mining program. Natural Language Toolkit.
NORM - Multiple imputation of multivariate continuous data under a normal model.

Octave - Similar to Matlab.
Onto-Tools - Bioinformatics programs. Onto-Express, Onto-Compare, Onto-Design, Onto-Translate, Onto-Miner, Pathway-Express, Promoter-Express, nsSNPCounter, OE2GO, KUTE-BASE.
OpenBUGS - Bayesian inference using Gibbs sampling.
Open Code - A tool for coding qualitative data generated from text information such as interviews, observations or field notes.
OpenEpi - Epidemiology package.
OpenOffice - Open source alternative to Microsoft Office. Includes Calc, an alternative to Excel.
Openstat - General stats package.
Orange - Data mining through visual programming or Python scripting. Extensions for bioinformatics and text mining.

PAMCOMP - Person-years And Mortality COMputation Program.
PAST - Statistics program for palaeontology.
PCP - Pattern Classification Program.
PINT - Power analysis IN Two-level designs (for determination of standard errors and optimal sample sizes in multilevel designs with 2 levels).
Ploticus - Graphs program.
PopTools - Population modelling program.
POSDEM - A program to choose between sampling plans based on the population frame.
PostgreSQL - Relational database management system (RDBMS).
PQRS - Stands for probabilities, quantiles and random samples.
Program Mark - Ecological statistics program. Advanced mark-recapture modelling.
PS - Power and sample size calculator.
PSPP - Alternative to SPSS.

QCA - Qualitative Comparative Analysis is a special-purpose program designed to analyze quantified data from multiple cases.
QPL - Questionnaire Programming Language.
Quail - Quantitative analysis in Lisp.

R - Widely used alternative to SPlus.
R Commander - GUI interface for R.
RapidMiner - Data mining.
Red R - Visual programming interface for R.
Regress+ - Mathematical modelling for the Macintosh.
RMAexpress - Bioinformatics software. A standalone GUI program to compute gene expression summary values for Affymetrix Genechip data.
Rosetta - A rough set toolkit for data analysis / data mining.
Rule Discovery System - Data mining program.
Rundom Pro - General stats package with emphasis on resampling procedures.
Rweb - An online form that processes R commands.

|STAT - General stats package.
Sage - Mathematics software.
SalStat - General stats package designed for the analysis of science and psychology data.
SAM - Bioinformatics software. Sequence Alignment and Modeling System.
Scilab - Numerical computation.
Shogun - A large scale machine learning toolbox.
Simfit - Simulation, curve fitting, statistics, and plotting.
Simplex Method Tool - An online form that solves linear programming problems.
SimulME - A Java ME (J2ME) application with queuing calculator, Monte Carlo simulation and more. Compatible with Sony-Ericsson, Samsung, Motorola and other cell phones.
SL Gallery - Statistical distribution graphs and calculations.
SOCR - Stands for statistics online computational resource. General stats package.
SOFA Statistics - Statistics, analysis and reporting program.
Software for Permutation Methods: A Distance Function Approach
Sonar - Survey administration and data collection system.
SpreadCE - Spreadsheet program.
SSP (Smith's Statistical Package) - General stats package.
StatCalc - A Calculator that computes table values of 34 statistical distributions. It also computes moments, and many other statistics.
StatEasy - General stats package.
Statext - Statistics expressed in text (even the graphs).
Statibot - An interactive www-based expert system for basic statistical analysis.
Statist - General stats package.
Statistical Lab - R based general stats package.
Statistics 101 - Simulations / resampling methods.
STATPerl - General stats package based on Perl.
Stattucino - Web spreadsheets with data analysis functions.

TAMS - Text mining program. Text Analysis Mark-up System. Identifies themes in texts.
Tanagra - Data mining.
TELPACK - Teletraffic Analysis Package.
Tetrad - Search algorithms and statistical modelling.
TextStat - Text concordance program. A program for the analysis of texts.
TimesLab - Time series analysis program.
TMeV - Bioinformatics software. Normalized and filtered expression files can be analyzed using TIGR Multiexperiment Viewer (MeV).
TSW - Time series and econometrics package.
TWOMOK - Non-parametric scale analysis for two-level data (ecometrics).

UIMA - Text mining program. Unstructured Information Management Architecture.
Ultrafind - Text concordance program. Extremely fast text search.

VARBRUL - Designed to facilitate analysis of linguistic variables and social variables.
VisiCube - Data visualisation tool.
ViSta - Visual statistics system with work maps, guide maps and interactive graphics.
VStar - Data visualisation and analysis tool for astronomy.

Weft QDA - A tool to assist in the analysis of textual data such as interview transcripts, written texts and field notes.
Weka - Machine learning software written at the University of Waikato.
WinBUGS - Bayesian analysis using Markov chain Monte Carlo methods.
WinIDAMS - General stats package.
Winpepi - Epidemiology package.
WordNet - A large lexical database of English.

X-12-ARIMA - Seasonal adjustment software produced, distributed, and maintained by the US Census Bureau.
XDAT - Visualization and analysis of multidimensional data.
XL Statistics - A set of Microsoft Excel (ver 97+) workbooks for statistical analysis of data.
XL Toolbox - Data analysis add-on for Excel.
Xnumbers - Multi precision floating point computing and numerical methods for Excel.
XploRe - Interactive statistical methods and data exploration.
Xpro - Exact parametric inference.
Xtremes - Graphics and analysis program for extreme values.

Yxilon - Statistical programming language.

Zaitun Time Series - Time series software. Has the capability to deal with stock market data.
Zelig - Based on R. Automates various processes.

A fonte original, com os links de cada software está aqui: http://l-lists.com/en/lists/dz3a5t.html

quarta-feira, 6 de março de 2013

Táxis elétricos começam a circular no Rio de Janeiro

Táxis elétricos começam a circular no Rio de Janeiro: Os veículos são do modelo Leaf, que têm uma autonomia de 160 km.

Iniciativas como esta mudam o cotidiano da sociedade, pois altera a forma de pensar dos indivduos e muda muitos aspectos ambientais e econmicos.

O uso de energia eltrica para abastecer carros vai alterar o preo da gasolina, talvez bareteando para torn-la uma opo atrativa ou encarecendo para compensar a perda de vendas.

O meio ambiente tambm ter suas alteraes, pela diminuio de poluentes, mas tambm pela necessidade de se produzir mais energia eltrica, neste caso  importante investir em formas de produo de energia que causem pouco impacto ambiental.

As pessoas sentiro as diferenas no conforto do carro, mas silencioso e sem vibraes do motor explodindo combustvel, com o tempo o ar ficar melhor respirvel e as novas geraes tero mais conscincia de como  importante assegurar a qualidade do meio ambiente, mesmo em centros urbanos.