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Actual Size (actual + size)
Selected AbstractsCalculating census efficiency for river birds: a case study with the White-throated Dipper Cinclus cinclus in the PyrénéesIBIS, Issue 1 2003Frank D'Amico Using the binomial law we modelled field data to estimate the probability (p,) of detecting pairs of breeding White-throated Dippers, and the population size (N,± confidence limits). The model was divided into two parts according to whether the actual size of the population under study was known or not; in the latter case the truncated binomial model was used. Dipper abundance data were collected from three 4-km-long river tracts in the Pyrénées (France) during the breeding seasons of different years. Goodness-of-fit tests indicated that the binomial model fitted the data well. For a given visit during the survey, the estimated probability of detecting any pair of Dippers if they were present was always high (0.63,0.94) and constant from year to year but not between sites. Estimations (N,) of the size of the population provided by the binomial model were very close to that derived from mapping techniques. This study provides the first ever quantification of the number of visits required to detect birds on linear territories: three visits were necessary to detect the whole breeding population. [source] Criterion knowledge: A moderator of using the recognition heuristic?JOURNAL OF BEHAVIORAL DECISION MAKING, Issue 5 2009Benjamin E. Hilbig Abstract The recognition heuristic (RH) claims that people base inferences on recognition only. This has been questioned by several studies which found that additional knowledge was influential. However, in some of these studies, participants' additional knowledge might have encompassed criterion knowledge thus rendering any inferential strategy superfluous. The present study was therefore designed to test the effect of criterion knowledge on use or non-use of the RH. Eighty-one participants made pair-wise comparisons with respect to the size of Belgian cities and also provided estimates of the cities' actual size. We found that relative criterion knowledge (i.e., knowledge about the relative position of an object on the criterion dimension) did indeed play some role, but its exclusion left the main critical findings intact, nonetheless. We thus conclude that previous studies conducted in the paradigm of natural recognition should not be generally refuted by the argument of participants possessing criterion knowledge. Copyright © 2009 John Wiley & Sons, Ltd. [source] Non-parametric permutation test for the discrimination of float glass samples based on LIBS spectraJOURNAL OF CHEMOMETRICS, Issue 6 2010Erin McIntee Abstract Laser-induced breakdown spectroscopy (LIBS) coupled with non-parametric permutation based hypothesis testing is demonstrated to have good performance in discriminating float glass samples. This type of pairwise sample comparison is important in manufacturing process quality control, forensic science and other applications where determination of a match probability between two samples is required. Analysis of the pairwise comparisons between multiple LIBS spectra from a single glass sample shows that some assumptions required by parametric methods may not hold in practice, motivating the adoption of a non-parametric permutation test. Without rigid distributional assumptions, the permutation test exhibits excellent discriminating power while holding the actual size of Type I error at the nominal level. Copyright © 2010 John Wiley & Sons, Ltd. [source] Interpreting and estimating measures of community phylogenetic structuringJOURNAL OF ECOLOGY, Issue 5 2008Olivier J. Hardy Summary 1To characterize the spatial phylogenetic structure of communities, Hardy & Senterre (2007) (J. Ecol., 95, 493,506) partition Gini,Simpson diversity and its generalization, Rao's entropy, defining IST and PST as the proportion of diversity expressed among sites. 2Interpreting IST as a measure of ,differentiation' between sites is inadequate because low values are actually compatible with high differentiation (low species sharing) in species rich communities. To avoid an inadequate use of IST, for example in conservation biology, we offer a more literal interpretation: IST expresses the ,local species identity excess'. Similarly, PST expresses the ,local phylogenetic similarity excess'. 3Villéger & Mouillot (2008) (J. Ecol., 96, 845,848, this issue) argue that the equations of Hardy & Senterre (2007) to compute diversity are inadequate when sites differ in size, and they provide new expressions weighting sites by their sizes. We argue that whether sites must be weighted equally or not depends on the question being asked. Moreover, actual size and sample size must be distinguished, the latter being important for defining estimators. 4Synthesis. The formulations given by Hardy & Senterre (2007) and by Villéger & Mouillot (2008) are both correct in the specific contexts we detail. [source] The effect of font and line width on reading speed in people with mild to moderate vision lossOPHTHALMIC AND PHYSIOLOGICAL OPTICS, Issue 6 2006Gary S. Rubin Abstract Purpose:, The aim of this study was to evaluate the effects of print size, typeface, and line width on reading speed in readers with mild to moderate sight problems. Methods:, A total of 43 patients, most of whom had mild cataract or glaucoma with acuity 6/30 or better (median age = 72; range = 24,88 years), read aloud a selection of texts presented randomly in four sizes (10, 12, 14 and 16 point), for each of four typefaces [Foundry Form Sans (FFS), Helvetica (HV), Tiresias PCfont (TPC), Times New Roman (TNR)] at a standard line width of 70 characters and a viewing distance of 40 cm. A subset of letter sizes and typefaces were tested at two additional line widths (35, 90). Results:, As expected, reading speed increased with print size from a median of 144 words min,1 for 10-point text to 163 words min,1 for 16-point text (repeated measures anova, p < 0.0001). There was also a significant effect of typeface with TPC being read about 8 words min,1 faster, on average, than the other fonts (159 words min,1 for TPC vs 151 words min,1 for the other fonts, p < 0.0001). However fonts of the same nominal point size were not equivalent in actual size. When adjusted for the actual horizontal and vertical space occupied, the advantage of TPC was eliminated. There was no effect of line width (p > 0.3). Data from the present study were extrapolated to the general population over age 65. This extrapolation indicated that increasing minimum print size from 10 points to 16 points would increase the proportion of the population able to read fluently (>85 words min,1) from 88.0% to 94.4%. Conclusion:, This study shows that line width and typeface have little influence on reading speed in people with mild to moderate sight problems. Increasing the minimum recommended print size from 10 points to 14 or 16 points would significantly increase the proportion of the population able to read fluently. [source] A shrew-sized origin for primatesAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue S39 2004Daniel L. Gebo Abstract The origin of primates has had a long history of discussion and debate, with few ever considering the impact of the original body weight on subsequent primate adaptive radiations. Here, I attempt to reconstruct early primate evolution by considering the initial size of primates as well as the critical functional-adaptive events that had to occur prior to the early Eocene. Microcebus is often viewed as a living model, and thus 40,65 g might represent a practical ancestral weight for the origin of primates. I consider a smaller original body weight, likely 10,15 g in actual size, and I address the biological implications for shrew-sized primates by comparing the behavioral ecology of mouse lemurs, our smallest living primates, to another tiny-sized mammalian group, the shrews (Family Soricidae). Several behavioral and ecological characteristics are shared by shrews and mouse lemurs, and several mammalian trends are evident with decreased size. I suggest that a shrew-sized ancestral primate would have had high metabolic, reproductive, and predation rates, relatively low population densities, and a dispersed and solitary existence with a promiscuous mating system. Although small mammals like shrews provide insights concerning the ancestral size of primates, primate origins have always been tied to arboreality. I assess other potential arboreal models such as Ptilocercus and Caluromys. By combining all of this information, I try to sequence the events in a functional-adaptive series that had to occur before the early Eocene primate radiations. I suggest that all of these important adaptive events had to occur at a small body size below 50 g. Yrbk Phys Anthropol 47:40,62, 2004. © 2004 Wiley-Liss, Inc. [source] Review of 125 SiteSelect Stereotactic Large-Core Breast Biopsy ProceduresTHE BREAST JOURNAL, Issue 3 2003Christa C. Corn MD Abstract: Advances in stereotactic breast biopsies have introduced a variety of devices that yield different sizes of tissue samples. The choice of biopsy device should be based on which technique is most likely to yield a definitive diagnosis at the time of the initial biopsy. This is a prospective study of 104 patients who underwent a total of 125 stereotactic breast biopsies using the SiteSelect large-core biopsy device. From May 1999 to June 2001, 104 patients underwent 125 stereotactic breast biopsies with the SiteSelect large-core biopsy device. One hundred four 15 mm SiteSelect biopsies, eighteen 10 mm SiteSelect biopsies, and three 22 mm SiteSelect biopsies were performed. Atypical ductal hyperplasia (ADH) and ductal carcinoma in situ (DCIS) were found in 15% of the biopsies and infiltrating cancer was found in another 15% of the biopsies. Seventy-eight percent of the ADH and 90% of the DCIS lesions were associated with indeterminate calcifications noted on mammogram. Two of the 22 mm SiteSelect excisions yielded a specimen that contained the entire cancer with clear surgical margins. All of the patients with DCIS or invasive carcinoma underwent definitive surgical and adjuvant therapy. The sensitivity and specificity of SiteSelect in this series of patients was 100%. The SiteSelect biopsy procedure is safe, well tolerated by patients, and can be performed under local anesthesia. SiteSelect is comparable to an open excisional biopsy in its ability to obtain adequate tissue for accurate diagnosis, but excises significantly less normal surrounding breast tissue. Based on the data, indications for primary use of SiteSelect are indeterminate calcifications on mammogram, rebiopsy of a vacuum-assisted biopsy site that yielded atypia on pathologic examination, and complete excision of a lesion suspicious for invasive carcinoma in order to assess actual size and margin status. [source] A Model of Spoils PoliticsAMERICAN JOURNAL OF POLITICAL SCIENCE, Issue 1 2009Ernesto Dal Bó Accounts of state failure in the developing world frequently highlight a logic of "spoils politics" in which a government and an opposing faction vie for control of the state and the accompanying spoils. Attempts to buy the opposition off play a key role in this logic, and an informational problem often complicates these efforts. Because of limited transparancy, the government generally has a better idea about the actual size of the spoils than the opposition does. We formalize this aspect of spoils politics as a signaling game in which the government has private information about the size of the spoils and tries to co-opt the opposition by offering a share of the spoils. The opposition can accept the offer or reject it by fighting. Consistent with the strong empirical finding that the probability of civil war is higher when income is low, the probability of breakdown increases as the size of the spoils decreases. We also study the effects of uncertainty, the opposition's military strength, the cost of fighting, and power-sharing agreements on the probability of fighting. [source] Census and monitoring based on individually identifiable vocalizations: the role of neural networksANIMAL CONSERVATION, Issue 2 2002Andrew M. R. Terry Vocal individuality is widely suggested as a method for identifying individuals within a population. But few studies have explored its performance in real or simulated conservation situations. Here we simulated the use of vocal individuality to monitor the calling corncrake (Crex crex), a secretive and endangered land rail. Our data set contained 600 calls from 30 individuals and was used to simulate a population of corncrakes being counted and monitored. We tested three different neural network models for their ability to discriminate between and to identify individuals. Neural networks are non-linear classification tools widely applied to both biological and non-biological identification tasks. Backpropagation and probabilistic neural networks were used to simulate the reidentification of members of a known population (monitoring) and a Kohonen network was used to simulate the counting of a population of unknown size (census). We found that both backpropagation and probabilistic networks identified all individuals correctly all the time, irrespective of sample size. Kohonen networks were more variable in performance but estimated population size to within one individual of the actual size. Our results indicate that neural networks can be used effectively together with recordings of vocalizations in census and monitoring tasks. [source] Measurement of optic disc parameters on digital fundus photographs: algorithm development and evaluationACTA OPHTHALMOLOGICA, Issue 8 2008Herman Bartling Abstract. Purpose:, To develop and evaluate a simple and rapid algorithm for optic disc measurements on digital fundus photographs, relying on the macula,disc centre distance as a reference when converting length expressed in pixels to metric distance. Methods:, Measurements were performed on fundus photographs from 68 normal subjects, acquired using five different cameras. The magnification factor and actual size in ,m of 1 pixel was known for only one camera. The measurements from this camera were compared to corresponding measurements from a confocal scanning laser ophthalmoscope. Results:, Using the described algorithm, no significant differences in mean disc or cup size were observed between the tested cameras, despite differences in magnification factor (range 0.5,2.5). There were no significant differences between disc and cup measurements obtained with the confocal scanning laser ophthalmoscope and those obtained with the described algorithm in the 20 subjects examined. Conclusion:, The algorithm described in the current study provided clinically relevant measurements of optic disc parameters. The final program can be used directly on the acquired images, with the examined subject still available for re-examination. [source] | |||||||||||||