# Posts Tagged ‘ statistics ’

## In Mexico, more marriages ending in divorce, and sooner

May 18, 2012
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R user Diego Valle analyzed the rate of divorces in Mexican marriage since 1993 (the earliest date for which data are available) and found that not only have more marriages ended in divorce over time, but marriages that do end are ending sooner: This chart is a bit complicated, but it bears close inspection. Each line you see is...

## Non transitivity of correlation for random vectors in dimension 3

May 18, 2012
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Dependence in dimension 2 is difficult. But one has to admit that dimension 2 is way more simple than dimension 3 ! I recently rediscovered a nice paper, Langford, Schwertman & Owens (2001), on transitivity of the property of being positively c...

## Criticism 4 of NHST: No Mechanism for Producing Substantive Cumulative Knowledge

May 18, 2012
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In this fourth part of my series of criticisms of NHST, I’m going to focus on broad

## Exponential decay models

May 17, 2012
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All models are wrong, some models are more wrong than others. The streetlight model Exponential decay models are quite common.  But why? One reason a model might be popular is that it contains a reasonable approximation to the mechanism that generates the data.  That is seriously unlikely in this case. When it is dark and … Continue reading...

## garch() uncertainty

May 16, 2012
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As part of an on-going paper with Kerrie Mengersen and Pierre Pudlo, we are using a GARCH(1,1) model as a target. Thus, the model is of the form which is a somehow puzzling object: the latent (variance) part is deterministic and can be reconstructed exactly given the series and the parameters. However, estimation is not

## Will 2015 be the Beginning of the End for SAS and SPSS?

May 15, 2012
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Learning to use a data analysis tool well takes significant effort, so people tend to continue using the tool they learned in college for much of their careers. As a result, the software used by professors and their students is … Continue reading →

## Blog aggregators

May 15, 2012
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A very useful way of keeping up with blogs in a particular area is to subscribe to a blog aggregator. These will syndicate posts from a large number of blogs and provide links back to the original sources. So you only need to subscribe once to get all the good stuff in that area. There are now several blog...

## generalised ratio of uniforms

May 14, 2012
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$generalised ratio of uniforms$

A recent arXiv posting of the paper “On the Generalized Ratio of Uniforms as a Combination of Transformed Rejection and Extended Inverse of Density Sampling” by Martino, Luengo, and Míguez from Madrid rekindled my interest in this rather peculiar simulation method. The ratio of uniforms samples uniformly on the subgraph to produce simulations from p

## Criticism 3 of NHST: Essential Information is Lost When Transforming 2D Data into a 1D Measure

May 14, 2012
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Introduction Continuing on with my series on the weaknesses of NHST, I’d like to focus on an issue that’s not specific to NHST, but rather one that’s relevant to all quantitative analysis: the destruction caused by an inappropriate reduction of dimensionality. In our case, we’ll be concerned with the loss of essential information caused by

## Criticism 2 of NHST: NHST Conflates Rare Events with Evidence Against the Null Hypothesis

May 12, 2012
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Introduction This is my second post in a series describing the weaknesses of the NHST paradigm. In the first post, I argued that NHST is a dangerous tool for a community of researchers because p-values cannot be interpreted properly without perfect knowledge of the research practices of other scientists — knowledge that we cannot hope