Posts Tagged ‘ English ’

Smaller or greater? – episode II

May 20, 2011
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Smaller or greater? – episode II

In a previous post I introduced the following game: Suppose you play the following game: Someone holds a set of cards with the numbers {1,2,…,N} in random order, opens up the first card and asks if the next card is greater or smaller. Every time you predict correctly, you get one point, while every wrong

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[Project Euler] – Problem 57

May 19, 2011
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It is possible to show that the square root of two can be expressed as an infinite continued fraction. √ 2 = 1 + 1/(2 + 1/(2 + 1/(2 + … ))) = 1.414213… By expanding this for the first four iterations, we get: Read More: 547 Words Totally

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Machine Learning Ex3 – Multivariate Linear Regression

March 29, 2011
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Machine Learning Ex3 – Multivariate Linear Regression

Part 1. Finding alpha. The first question to resolve in Exercise 3 is to pick a good learning rate alpha. This require making an initial selection, running gradient descent and observing the cost function. Read More: 221 Words Totally

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clusterProfiler in Bioconductor 2.8

March 26, 2011
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In recently years, high-throughput experimental techniques such as microarray and mass spectrometry can identify many lists of genes and gene products. The most widely used strategy for high-throughput data analysis is to identify different gene clusters based on their expression profiles. Another commonly used approach is to annotate these genes to biological knowledge, such as Gene Ontology (GO) and...

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Machine Learning Ex2 – Linear Regression

March 22, 2011
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Machine Learning Ex2 – Linear Regression

Thanks to this post, I found OpenClassroom. In addition, thanks to Andrew Ng and his lectures, I took my first course in machine learning. These videos are quite easy to follow. Exercise 2 requires implementing gradient descent algorithm to model data with linear regression. Read More: 243 Words Totally

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The easiest way to get UTR sequence

March 2, 2011
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I just figure out the way to query UTR sequence from ensembl by biomart tool. It is very simple compare with using bioperl to parse gbk file to extract UTR sequence. Read More: 232 Words Totally

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The easiest way to get UTR sequence

March 2, 2011
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I just figure out the way to query UTR sequences from ensembl by biomart tool. It is very simple compared with using bioperl to parse gbk files to extract UTR sequences. Read More: 236 Words Totally

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Estimate Probability and Quantile

January 25, 2011
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Simple root finding and one dimensional integrals algorithms were implemented in previous posts. These algorithms can be used to estimate the cumulative probabilities and quantiles. Here, take normal distribution as an example. Read More: 281 Words Totally

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Estimate Probability and Quantile

January 25, 2011
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Simple root finding and one dimensional integrals algorithms were implemented in previous posts. These algorithms can be used to estimate the cumulative probabilities and quantiles. Here, take normal distribution as an example. Read More: 281 Words Totally

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Single variable optimization

January 1, 2011
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Optimization means to seek minima or maxima of a funtion within a given defined domain. If a function reach its maxima or minima, the derivative at that point is approaching to 0. If we apply Newton-Raphson method for root finding to f’, we can get the optimizing f. Read More: 223 Words Totally

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