Blog Archives

R: Mapping Philippine Earthquakes (October 2013)

November 5, 2013
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R: Mapping Philippine Earthquakes (October 2013)

Last month, October 15, 2013 around 8:12 am (Philippine Time), a magnitude 7.2 earthquake hit Bohol island, detroying several infrastructures and killing hundreds of residents. The Philippine Institute of Volcanology and Seismology or PhiVolcs recorde...

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R: Mapping Typhoon Labuyo (Utor) Track

October 14, 2013
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R: Mapping Typhoon Labuyo (Utor) Track

Inspired by James Cheshire R maps, I tried mapping the track of Typhoon Labuyo (Utor) that by far the strongest one to hit Philippines this year. The data is available at Japan Meteorological Agency site, the 2013 - RSMC Best Track data. The code is av...

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Interval Estimation of the Population Mean

June 14, 2013
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Interval estimation of the population mean can be computed from the functions of the following R packages:stats - contains the t.testTeachingDemos - contains the z.testBSDA - contains the zsum.test and tsum.testThe t.test of the stats package is a stud...

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Measures of Skewness and Kurtosis

June 10, 2013
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Measures of Skewness and Kurtosis

Skewness and kurtosis in R are available in the moments package (to install an R package, click here), and these are:Skewness - skewnessKurtosis - kurtosisExample 1. Mirra is interested in the elapse time (in minutes) she spends on riding a tricycle fr...

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Measure of Relative Variability

June 10, 2013
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The measure of relative variability is the coefficient of variation (CV). Unlike measures of absolute variability, the CV is unitless when it comes to comparisons between the dispersions of two distributions of different units of measurement. In R, CV ...

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Measures of Absolute Variability

June 10, 2013
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Measures of absolute variability deal with the dispersion of the data points. This include the following:Range - rangeInterquartile Range - IQRQuartile DeviationAverage DeviationStandard Deviation - sdThese measures of variability restrict to uniform u...

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Quartiles, Deciles, and Percentiles

June 9, 2013
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The measures of position such as quartiles, deciles, and percentiles are available in quantile function. This function has a usage,where:x - the data pointsprob - the location to measurena.rm - if FALSE, NA (Not Available) data points are not ignoredna...

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Mean and Median

June 8, 2013
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Mean in R is computed using the function mean. Consider the scores of 20 MSU-IIT students in Stat 101 exam with a hundred items: 70, 78, 66, 65, 50, 53, 48, 88, 95, 80, 85, 84, 81, 63, 68, 73, 75, 84, 49, and 77. Compute and interpret the mean and medi...

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Matrix Operations

June 8, 2013
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Matrix manipulation in R are very useful in Linear Algebra. Below are lists of common yet important functions in dealing operations with matrices:Transpose - tMultiplication - %*%Determinant - detInverse - solve, or ginv of MASS libraryEigenvalues and ...

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Data Class Conversion

June 6, 2013
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Data in R can be converted from one class to the other. The function is prefixed with as. then followed by the name of the data class that we wish to convert to. Data class in R are the following:numeric - as.numericvector - as.vectorcharacter - as.cha...

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