169 research outputs found
Frequency data from corpora partially explain native-speaker ratings and choices in overabundant paradigm cells
If we can operationalize corpus frequency in multiple ways, using absolute values and proportional values, which of them is more closely connected with the behaviour of language users? In this contribution, we examine overabundant cells in morphological paradigms, and look at the contribution that frequency of occurrence can make to understanding the choices speakers make due to this richness. We look at ways of operationalizing the term frequency in data from corpora and native speakers: the proportional frequency of forms (i.e. percentage of time that a variant is found in corpus data considered as a proportion of all variants) and several interpretations of absolute frequency (i.e. the raw frequency of variants in data from the same corpus). Working with data from unmotivated morphological variation in Czech case forms, we show that different instantiations of frequency help interpret the way variation is perceived and maintained by native speakers. Proportional frequency seems most salient for speakers in forming their judgements, while certain types of absolute frequency seem to have a dominant role in production tasks
Studying negative evidence in Finnish language corpora
This study explores the relationship between lower-than-expected frequencies of word forms and inherent gaps in Finnish inflectional paradigms. The research aims to determine whether it is possible to predict paradigmatic gaps from lower-than-expected frequencies of word forms. We examined Finnish nouns inflected in a marginal case (the instructive) and hypothesized that some of these nouns may potentially have gaps in their inflectional paradigms. However, we found that such gaps are contingent and do not cause uncertainty when filled. We find that the correlation between inherent gaps and lower frequencies is one-directional: predicting inherent gaps from lower-than-expected frequencies is problematic. The results suggest that any paradigmatic gap suggested by corpus frequency is more likely to be contingent than inherent, and that the less semantic need there is for a particular word form, the more likely it will be unattested even in a large corpus. The research highlights the importance of considering semantic profiles when analyzing the grammaticality of word forms and suggests that statistical tests like Fisher’s exact are not necessarily the right approach to tackle the problem of negative evidence in corpus studies
Morphological variation and sensitivity to frequency of forms among native speakers of Czech
This article looks at inter-speaker variation in two environments: the genitive and locative singular cases of masculine ‘hard inanimate’ nouns in Czech, using a large-scale survey of native speakers that used two tasks to test their preferences for certain forms (acceptability) and their choices (gap filling). Our hypothesis that such variation exists was upheld, but only within limited parameters. Most biographical data (age, gender, education) played no role in respondents’ choices or preferences. Their region of origin played a small but significant role, although not the one expected. Relating the two types of tasks to each other, we found that respondents’ use of the ratings scale did not correlate to their choice of forms, but their overall strength of preference for one form over another did correlate with their choices. Inter-speaker variation does thus go some way to explaining the persistent diversity in this paradigm and arguably may contribute to its maintenance
Do users’ reading skills and difficulty ratings for texts affect choices and evaluations?
In our contribution, we consider how corpus data can be used as a proxy for the written language environment around us in constructing offline studies of native-speaker intuition and usage. We assume a broadly emergent perspective on language: in other words, the linguistic competence of individuals is not identical or hardwired but forms gradually through exposure and coalescence of patterns of production and reaction. We hypothesize that while users presumably all in theory have access to the same linguistic material, their actual exposure to it and their ability to interpret it may differ, which will result in differing judgments and choices. Our study looks at the interaction between corpus frequency and two possible indicators of individual difference: attitude towards reading tasks and performance on reading tasks. We find a small but consistent effect of task performance on respondents’ judgments but do not confirm any effects on respondents’ production tasks
Uncertainty in the production of Czech noun and verb forms
We examine the reactions of Czech native speakers to cues asking them to supply inflectional forms of nouns and verbs that are either canonical (non-variant), overabundant, or supposedly defective, to see what distinguishing characteristics these three conditions have for
production. We find that respondents handle defective material differently from other conditions, producing different sorts of forms at different frequencies, and taking significantly longer to do so. Overabundant cells pattern at the individual level like canonical
inflectional cells, but collectively display a significantly more varied and less focused spread of forms produced than our canonical cells. The individual dimension of uncertainty in production is thus limited to defective cells, but the collective dimension of uncertainty is evident between all three conditions
Tailoring optical nonlinearities via the Purcell effect
We predict that the effective nonlinear optical susceptibility can be
tailored using the Purcell effect. While this is a general physical principle
that applies to a wide variety of nonlinearities, we specifically investigate
the Kerr nonlinearity. We show theoretically that using the Purcell effect for
frequencies close to an atomic resonance can substantially influence the
resultant Kerr nonlinearity for light of all (even highly detuned) frequencies.
For example, in realistic physical systems, enhancement of the Kerr coefficient
by one to two orders of magnitude could be achieved
13C-direct detected NMR experiments for the sequential J-based resonance assignment of RNA oligonucleotides
We present here a set of 13C-direct detected NMR experiments to facilitate the resonance assignment of RNA oligonucleotides. Three experiments have been developed: (1) the (H)CC-TOCSY-experiment utilizing a virtual decoupling scheme to assign the intraresidual ribose 13C-spins, (2) the (H)CPC-experiment that correlates each phosphorus with the C4′ nuclei of adjacent nucleotides via J(C,P) couplings and (3) the (H)CPC-CCH-TOCSY-experiment that correlates the phosphorus nuclei with the respective C1′,H1′ ribose signals. The experiments were applied to two RNA hairpin structures. The current set of 13C-direct detected experiments allows direct and unambiguous assignment of the majority of the hetero nuclei and the identification of the individual ribose moieties following their sequential assignment. Thus, 13C-direct detected NMR methods constitute useful complements to the conventional 1H-detected approach for the resonance assignment of oligonucleotides that is often hindered by the limited chemical shift dispersion. The developed methods can also be applied to large deuterated RNAs
Revisiting Brain Atrophy and Its Relationship to Disability in Multiple Sclerosis
Brain atrophy is a well-accepted imaging biomarker of multiple sclerosis (MS) that partially correlates with both physical disability and cognitive impairment.Based on MRI scans of 60 MS cases and 37 healthy volunteers, we measured the volumes of white matter (WM) lesions, cortical gray matter (GM), cerebral WM, caudate nucleus, putamen, thalamus, ventricles, and brainstem using a validated and completely automated segmentation method. We correlated these volumes with the Expanded Disability Status Scale (EDSS), MS Severity Scale (MSSS), MS Functional Composite (MSFC), and quantitative measures of ankle strength and toe sensation. Normalized volumes of both cortical and subcortical GM structures were abnormally low in the MS group, whereas no abnormality was found in the volume of the cerebral WM. High physical disability was associated with low cerebral WM, thalamus, and brainstem volumes (partial correlation coefficients ~0.3-0.4) but not with low cortical GM volume. Thalamus volumes were inversely correlated with lesion load (r = -0.36, p<0.005).The GM is atrophic in MS. Although lower WM volume is associated with greater disability, as might be expected, WM volume was on average in the normal range. This paradoxical result might be explained by the presence of coexisting pathological processes, such as tissue damage and repair, that cause both atrophy and hypertrophy and that underlie the observed disability
Cerebral atrophy as outcome measure in short-term phase 2 clinical trials in multiple sclerosis
Cerebral atrophy is a compound measure of the neurodegenerative component of multiple sclerosis (MS) and a conceivable outcome measure for clinical trials monitoring the effect of neuroprotective agents. In this study, we evaluate the rate of cerebral atrophy in a 6-month period, investigate the predictive and explanatory value of other magnetic resonance imaging (MRI) measures in relation to cerebral atrophy, and determine sample sizes for future short-term clinical trials using cerebral atrophy as primary outcome measure
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