ooacquire 0.1.2

This is the second release of package ‘ooacquire’. It is an important update as it include bug fixes and enhancements which have some (minor) effect on the calculated spectral values. The update also removes some spurious warnings and has additional documentation, although not yet in final form.This package allows the acquisition of spectral data from spectrometers from Ocean Optics connected through the OmniDriver run-time, which is available at no cost from Ocean Optics. The current version implements several corrections and measuring protocols unavailable elsewhere in a single modular framework. Some of these cannot be used off-the-shelf as they require the characterisation and calibration of each individual spectrometer, so as to obtain usable values for constants. However, once these constants are available they can be passed as data arguments without need to modify the package itself. Functions are provided for spectral irradiance, spectral transmittance and spectral reflectance measurements. As transmittance and reflectance measurements are normally done relative to reference objects the calibration requirements are less involved than for spectral irradiance.

The package is available through r4photobiology repository.

Please raise issues concerning bugs or enhancements to this package through Bitbucket at https://bitbucket.org/aphalo/ooacquire/issues

A manuscript from 1987

Yesterday I found a copy of one of the first manuscripts I ever submitted. It was never published, so it is time for it to be made available. Ideas discussed are nowadays common place. The manuscript, I think, is still mostly valid almost 30 years after I wrote it… I should have tried harder to get it published then.

Click on the image to read the full manuscript.

Points of significance: P values and the search for significance

Source: Points of significance: P values and the search for significance : Nature Methods : Nature Research

This article discusses an important issue about the use of P-values and complements the articles I linked to last year in posts at this site.

Recommended reading.

The posts from last year were The American Statistical Association Says No to p-values, The American Statistical Association Says [Mostly] No to p-values, The debate continues: “It’s Not The P-values’ Fault”, P-values: the Continuing Saga, and More about P-values: what are the alternatives?

Nature article is wrong about 115 year limit on human lifespan – NRC

 

Leading scientific journal Nature reported on Wednesday about a maximum lifespan for humans. But are their statistics right?

Source: Nature article is wrong about 115 year limit on human lifespan – NRC

 

A small set observations with a few extreme observations plus subjective splitting of a data set into two subsets to be fitted separately to a linear regression model resulted in very clear cut conclusions and striking figures. However, none of this is solid evidence, or evidence at all supporting the paper’s conclusions. This series of articles, not only discusses the problems in the paper, but more importantly, it traces the review process that allowed it to be published in Nature.

A new analysis of the data appears in an article at “Ask a Swiss” but still based on model fitting. They detect a significant change in slope, but still we do not have confidence bands available.