Testing for equality of rates of evolution

Paleobiology ◽  
1987 ◽  
Vol 13 (3) ◽  
pp. 272-285 ◽  
Author(s):  
Jennifer A. Kitchell ◽  
George Estabrook ◽  
Norman MacLeod

A new method of data analysis offers a potentially powerful tool for statistically evaluating hypotheses of rate in temporally-ordered evolutionary phenomena. We present a method for bootstrapping time-ordered data sets to test hypotheses of the equality of rate. This method is applicable to both nonrandom and random generative processes. The method is applied to the data of Malmgren et al. (1983) for the Globorotalia plesiotumida–G. tumida planktonic foraminiferan lineage and the data of Reyment (1982) for the benthonic foraminiferan Afrobolivina afar. G. plesiotumida is recognizable on the basis of independent data as a species distinct from G. tumida, its descendant. Evolutionary change rate during the evolution of G. tumida from G. plesiotumida is shown to be faster than rates within either species. The pattern of variation exhibited by A. afar includes a time interval of more rapid change; this more rapid change is observed post hoc. A bootstrapping model based on post hoc observations reveals the rate in this time interval to be not significantly faster than expected in such post hoc intervals.

2019 ◽  
Author(s):  
Jessie Martin ◽  
Jason S. Tsukahara ◽  
Christopher Draheim ◽  
Zach Shipstead ◽  
Cody Mashburn ◽  
...  

**The uploaded manuscript is still in preparation** In this study, we tested the relationship between visual arrays tasks and working memory capacity and attention control. Specifically, we tested whether task design (selection or non-selection demands) impacted the relationship between visual arrays measures and constructs of working memory capacity and attention control. Using analyses from 4 independent data sets we showed that the degree to which visual arrays measures rely on selection influences the degree to which they reflect domain-general attention control.


BMC Cancer ◽  
2007 ◽  
Vol 7 (1) ◽  
Author(s):  
James E Korkola ◽  
Ekaterina Blaveri ◽  
Sandy DeVries ◽  
Dan H Moore ◽  
E Shelley Hwang ◽  
...  

Genetics ◽  
1976 ◽  
Vol 83 (2) ◽  
pp. 341-354
Author(s):  
Burt Singer ◽  
Ruth Sager ◽  
Zenta Ramanis

ABSTRACT A novel mapping procedure is presented for organelle genes or any other genetic system exhibiting a measurable frequency of exchanges occurring at a constant rate over a measurable time interval. For a set of markers in a multiply-marked cross, the exchange rates measure relative map distances from a centromere-like attachment point. With this method, we present mapping data and a linear map of genes in the chlcroplast genome of Chlamydomonas. The data are plotted as log (percent remaining heterozygotes) against time and map distances are taken as proportional to slope. A statistical method which is an adaptation of jackknife methodology to a regression problem was developed to estimate slope values. A single line is fitted to pooled data for each marker from several crosses, and then lines are re-fit to a series of pooled data sets in each of which the observations from a single cross have been omitted. From these data sets a final summary slope is computed as well as a statement of its variability. The relative positions of new markers present in single crosses can then be estimated utilizing data from many crosses. The method does not distinguish between one-armed and two-armed linear or circular maps. However, evaluation of this map in conjunction with cosegregation frequency data (Sager and Ramanis 1976b) provides unambiguous evidence of the genetic circularity of the Chlamydomonas chloroplast genome.


Author(s):  
R. R. Colditz ◽  
R. M. Llamas ◽  
R. A. Ressl

Change detection is one of the most important and widely requested applications of terrestrial remote sensing. Despite a wealth of techniques and successful studies, there is still a need for research in remote sensing science. This paper addresses two important issues: the temporal and spatial scales of change maps. Temporal scales relate to the time interval between observations for successful change detection. We compare annual change detection maps accumulated over five years against direct change detection over that period. Spatial scales relate to the spatial resolution of remote sensing products. We compare fractions from 30m Landsat change maps to 250m grid cells that match MODIS change products. Results suggest that change detection at annual scales better detect abrupt changes, in particular those that do not persist over a longer period. The analysis across spatial scales strongly recommends the use of an appropriate analysis technique, such as change fractions from fine spatial resolution data for comparison with coarse spatial resolution maps. Plotting those results in bi-dimensional error space and analyzing various criteria, the “lowest cost”, according to a user defined (here hyperbolic) cost function, was found most useful. In general, we found a poor match between Landsat and MODIS-based change maps which, besides obvious differences in the capabilities to detect change, is likely related to change detection errors in both data sets.


2020 ◽  
Vol 6 (1) ◽  
pp. 86-93
Author(s):  
R. Ivakin ◽  
Y. Ivakin ◽  
S. Potapichev

Geochronological tracking is an effective information technology for digital cartographic spatial data sets processing. It is widely known in retrospective patterns research about geographic relocation of figures, or any other units for a given time interval. Software component of geochronological tracking is becoming one the most popular GIS-integrated applications. The article presents the basic provisions for the algorithmization of the geochronological tracking procedure for statistical testing of retrospective studies hypotheses. We can observe the results of solving this optimization problem in a general form and in a number of the most typical variants. The obtained results of solving the optimization problem are interpreted in terms of the retrospective studies subject area. There are shown the ways of further practical application of the optimized algorithm in the tasks of modern logistics, data mining and formalized knowledge.


2020 ◽  
Vol 20 ◽  
pp. 01001
Author(s):  
Krisdianto Slamat ◽  
Pahmi Anshary ◽  
Anang Kadarsyah ◽  
Ika Oksi Susilawati

Barito River crosses from the northeast of Central Kalimantan province, but almost two-third of 1000 km length lies in South Kalimantan. While water comes from Schwaner Mountain in the upper, this river receives water from Meratus pass through five big rivers, such as Tabalong, Batang Alai, Pagat, Amandit, and Riam Kiwa. Before the water flowed into Barito River, it retains for sometimes in the low land swampy area, forming huge lowland muddy into shallow lakes, simply named wetlands. How do people commit to sustainability living in extreme tropical wetlands for generations? The ecological investigation was conducted for 2016 – 2019, in-situ observation on the daily life-behavior of local people of 200 local people living Barito Kuala, Tapin, Hulu Sungai Selatan, Hulu Sungai Tengah, Hulu Sungai Utara residences, their technologies, their progress in sustainability development. Data was collected by interviewing directly to the local, face to face, meeting with family, observing and confirming nature with them, as well as studying scientific articles and grey literature from official reports. Statistical calculation helps to compare several data sets, as well as serial of photographs, which documented to support the evidence visually. In conclusion, the locals face the rapid change environments which influence their life, income, health, and their properties and prosperity. Mostly, they complain that life is much more difficult now than several decades ago.


2000 ◽  
Vol 55 (5-6) ◽  
pp. 399-409 ◽  
Author(s):  
Olivier Raymond ◽  
Jean-Louis Fiasson ◽  
Maurice Jay

Fifteen Rosa cultivated races were described by means of phenotypic frequencies (11 tables). Two groups of correlated contingency tables were identified by ACT-STATIS (Analyse Conjointe de Tableaux - Structuration de Tableaux à Trois Indices de la Statistique) interstructure analysis. Three data sets appeared to be independent from the others. Typologies of races were obtained after ACT-STATIS compromise analyses for the two groups of correlated tables, and after Principal Component Analyses for the independent data sets. Each typology was original and variously influenced by genealogical structure, mutation or artificial selection pressures. A weighted synthesis was attempted in order to build a taxonomy of races taking into account these diversity factors. The good agreement between the resulting classification and the assumptions about the history of Rosa domestication advocated for a wider utilization of ACT-STATIS and RV coefficient when the relationships between individuals or populations have to be studied on the basis of their similarities.


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