2643 search results for "GIS"

More Beautiful Growth of $1 Chart

February 6, 2012
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More Beautiful Growth of $1 Chart

With all my recent focus on reporting and visualization, you might think that I have the investments all figured out.  Unfortunately, that is not the case, and I will resume more standard investment and systems posts soon.  I did want to shar...

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General Bayesian estimation using MHadaptive

February 6, 2012
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General Bayesian estimation using MHadaptive

If you can write the likelihood function for your model, MHadaptive will take care of the rest (ie. all that MCMC business). I wrote this R package to simplify the estimation of posterior distributions of arbitrary models. Here’s how it works: 1) Define your model (ie the likelihood * prior). In this example, lets build

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Accelerating analytics at MSU with Revolution R Enterprise

February 3, 2012
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Erik Sigur, Information Technologist for the Department of Statistics and Probability at Michigan State University, writes at ReadWriteWeb about using Revolution R Enterprise to provide high-performance computation in R to the researchers in his department: Our search for a more effective version of R ultimately brought us to a product called Revolution R Enterprise by Revolution Analytics, which provides...

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Monty Hall by simulation in R

February 3, 2012
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Monty Hall by simulation in R

(Almost) every introductory course in probability introduces conditional probability using the famous Monte Hall problem. In a nutshell, the problem is one of deciding on a best strategy in a simple game. In the game, the contestant is asked to select one of three doors. Behind one of the doors is a great prize (free

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Great Maps with ggplot2

February 2, 2012
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Great Maps with ggplot2

The above map (and this one) was produced using R and g

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Cochran Q Test for k related samples in R

February 1, 2012
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Cochran Q Test for k related samples in R

To run the Cochran Q Test in R, we need to download the package of it first, since it is not built-in in R. The name of the package is RVAideMemoire authored by Maxime Hervé. Here's how to do it.Codes:Here we are installing the package named RVAideMem...

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Confirming SSR, SSE, and SST using matrix in R

February 1, 2012
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Confirming SSR, SSE, and SST using matrix in R

The codes below was done in our regression laboratory class. Here, we run first the data in SPSS, and take the ANOVA output where we can find the computed values of SSR, SSE, and SST.ANOVAb Model Sum of Squares df Mean Square F Sig. 1 Regress...

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Example: Two Sample t-Test

January 31, 2012
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Example: Two Sample t-Test

The recovery time (in days) is measured for 10 patients taking a new drug and for 10 different patients taking a placebo. We wish to test the hypothesis that the mean recovery time for patients taking the drug is less than for those taking placebo. The...

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Given a room with n people in it, what is the probability any two will have the same birthday?

January 31, 2012
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Given a room with n people in it, what is the probability any two will have the same birthday?

Revisiting a fun puzzle I remember first encountering as an undergraduate. Nice example of creating a plot in R using ggplot2. I also plot the probability of someone in the room having the same birthday as you.

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Example: One Sample t-Test

January 31, 2012
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Example: One Sample t-Test

Using the stack loss dataset, test the hypothesis that the mean of the stackloss is equal to 20 versus a two-sided alternative. Solution:Codes:Output:Interpretation: With the p-value greater than the level of significance alpha at 0.05, then we la...

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