search for: populus

Displaying 7 results from an estimated 7 matches for "populus".

Did you mean: populous
2010 Nov 09
2
new column from column in another df
If I have a data frame where a species occupies several rows with different phases such as (both col's ar factors): species,phase Populus tremula,1 Populus tremula,2 Populus tremula,3 Calluna vulgaris,1 Calluna vulgaris,2 Betula alba,1 Betula alba,2 Betula alba,3 Primula veris,1 Primula veris,2 and another df where each species only have one row: species,growth_form Populus tremula,tree Acer platanoides,tree Ribes rubrum,shrub Callu...
2003 May 31
0
logistic regression
...accuracy | A = 94.9% B = 82.3% | A = 94.7% B = 83.3% std.dev. | 2.3% 15.4% | 2.6% 13.2% avg. AIC | 707 | 124 As I understand instead of augmenting the successes on the rare class, which I did not observe, I am sinply down-weighting the successes on the populus class. The populations can be thought as equal, and only the sample sizes are unbalanced. I was hoping that the continuity of the Binomial for N in [0,1] ans X in [0,1] could guarantee me that my results still make sense, but I am not sure. Any thoughts? Thanks Edo
2003 May 31
0
logistic regression (weights)
...d.dev. | 2.3% 15.4% | 2.6% 13.2% avg. AIC | 707 | 124 As I understand, non-integer weights are more respectful of what I observe since instead of augmenting the successes on the rare class, which I did not observe, they simply down-weight the successes on the populus class. The populations can be thought as equal, and only the sample sizes are unbalanced. Predictions also look better, so I was hoping that the continuity of the Binomial for N in [0,1] ans X in [0,1] could guarantee me that my results still make sense, but I am not sure. Any thoughts? Thanks...
2007 Apr 25
0
Split column of concatenated data
...iated Nat Street --- Nathaniel Street ???????? University of Southampton ???????? Plants and Environment Lab ????? School of Biological Sciences ?? Basset Crescent East ?? Southampton ?SO16 7PX ?????? tel: +44 (0) 2380 594268 ? fax: +44 (0) 2380 594269 ?n.r.street at soton.ac.uk ??? http://www.populus.biol.soton.ac.uk/~nat http://del.icio.us/n.r.street
2008 Feb 08
1
Can I index a dataframe with a reference from/to a second dataframe?
...alustris", "Fagus grandifolia", "Fraxinus americana", "Fraxinus nigra", "Lonicera canadensis", "Ostrya virginiana", "Picea glauca", "Picea mariana", "Pinus resinosa", "Pinus strobus", "Populus tremuloides", "Prunus serotina", "Prunus virginiana", "Quercus rubra", "Ribes ", "Sorbus americana", "Thuja occidentalis", "Tilia americana", "Tsuga canadensis", "Ulmus americana", "Vi...
2009 Jul 28
4
How to do poisson distribution test like this?
Dear R-listers, I want to reperfrom a poisson distribution test that presented in a recent-published biological research paper (Plant Physiology 2008, vol 148, pp. 1189-1200). That test is about the occurrence number of a kind of gene in separate chromosomes. For instance: The observed gene number in chromosome A is 36. The expected gene number in chromosome A is 30. Then, the authors got a
2008 Aug 05
0
P values in non linear regression and singular gradients using nls
...---- Message: 41 Date: Mon, 4 Aug 2008 09:26:40 +0200 From: MORNEAU Fran?ois <francois.morneau at ifn.fr> Subject: Re: [R] graph To: "elyakhlifi mustapha" <elyakhlifi_mustapha at yahoo.fr> Cc: r-help at r-project.org Message-ID: <5E3D22A4869BB94AA1138AB97660D8B6013CF672 at POPULUS.ifn.fr> Content-Type: text/plain; charset="iso-8859-1" Hello, Is ?segments what you are looking for ? Fran?ois -----Message d'origine----- De?: r-help-bounces at r-project.org [mailto:r-help-bounces at r-project.org] De la part de elyakhlifi mustapha Envoy??: vendredi 1 ao?t 20...