NDVI, risk assessment and developing countries

The Normalized Difference Vegetation Index (NDVI) estimates the greenness of plants covering the surface of the Earth by measuring the light reflected by the vegetation into space. The main idea behind the NDVI is that visible and near-infrared light is absorbed in different proportions by healthy and unhealthy plants: a green plant will reflect 50% of the near infrared-light it receives and only 8% of the visible light while an unhealthy plant will reflect respectively 40% and 30%. NDVI can then be used to quantitatively compare vegetation conditions across time and space (and indeed is quite widely used, a Google Scholar search on NDVI produced 60,500 hits).

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Thursday, 14 February 2013

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  • Why R? 2021 Invited Talks
    This year we are organizing the fifth edition of Why R? 2021 conference. As the meetings are held in English we invite R users from all over the globe! The program is available on our youtube.com/WhyRFoundationVideos channel. Go and check what lecture... Continue reading: Why R? 2021 Invited Talks

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    Knowing that I’m a fan of Stanislaw Ulam, X pointed me to an announcement of a recent movie, Les Aventures d’un Mathématicien, par Thor Klein. I was curious so I googled and found this inadvertently hilarious blurb: The warmhearted story … Continue reading →