Small samples

Since the late 1990s, voluntary travel behaviour change (VTBC) has been an increasingly popular strategy in Australia, applied to reduce both reliance on the car and greenhouse gas emissions. Early efforts to evaluate the impact of this strategy were generally implemented by the agency that also implemented the policy and used small sample, self-report surveys. The paper starts out by discussing the nature and size of travel behaviour changes that are frequently expected in current policy, noting that these are often smaller than the sampling and measurement errors in traditional methods of measuring travel behaviour. The paper then discusses some alternative methods of evaluating voluntary travel behaviour change implementations using panels to reduce sampling error, and using a combination of personal Global Positioning System devices and odometer reading surveys to measure travel patterns. From these considerations, a number of guidelines are suggested for what is required to evaluate voluntary travel behaviour change. The paper describes three recent case studies in Australia in which such methods have been used and evaluates the methodological approaches used in these studies against the suggested guidelines.

Substrate reduction therapy (SRT) is considered to be a potential therapeutic option for juvenile GM2 gangliosidosis (jGM2g). We evaluated the efficacy of SRT in jGM2g, assessing neurological, neuropsychological and brain magnetic resonance imaging (MRI) outcomes over a 24-month period of treatment. In an open-label and single-center study, five jGM2g patients (mean age 14.6+/-4.5 years) received oral miglustat at doses of 100-200mg t.i.d. adjusted to body surface area. Patients underwent general and neurological examinations, neuropsychological, electrophysiological, and brain MRI studies. All patients showed neurological deterioration over the period of the study, with particularly notable worsening of gait, speech and coordination. One patient experienced acute psychosis, and another showed worsening of pre-existing epilepsy. Some neuropsychological tests showed no evidence of deterioration in the three patients with high enough cognitive functioning for reliable assessment. Profound cognitive impairment in two children precluded neuropsychological evaluation. In four patients, evaluation of brain MRI showed no changes in white matter signal abnormalities and cerebellar atrophy noted at baseline, while one patient showed progression of cerebellar and supratentorial brain atrophy. Transmission electron microscopy analysis of peripheral mononuclear cells showed reduction of intracytoplasmatic inclusions with treatment. SRT with miglustat of patients with jGM2g failed to ameliorate progressive neurological deterioration, but apparently no worsening of some areas of cognitive function tested and brain MRI lesions was noted over 24 months of treatment. The results must be interpreted with care owing to the small sample of patients and the lack of a control-arm.

Reconstructions of foraging behavior and diet are central to our understanding of fossil hominin ecology and evolution. Current hypotheses for the evolution of the genus Homo invoke a change in foraging behavior to include higher quality foods. Recent microwear texture analyses of fossil hominin teeth have suggested that the evolution of Homo erectus may have been marked by a transition to a more variable diet. In this study, we used microwear texture analysis to examine the occlusal surface of 2 molars from Dmanisi, a 1.8 million year old fossil hominin site in the Republic of Georgia. The Dmanisi molars were characterized by a moderate degree of surface complexity (Asfc), low textural fill volume (Tfv), and a relatively low scale of maximum complexity (Smc), similar to specimens of early African H. erectus. While caution must be used in drawing conclusions from this small sample (n = 2), these results are consistent with continuity in diet as H. erectus expanded into Eurasia.

... As part of a study to identify children with autism prospectively at 18 months of age (Baird and Baron), we assessed a small comparison group of typically developing infants on experimental tasks of joint attention, imitation, and play at 20 months (Charman; Charman and ...

The aim of this paper is to study properties of the Kwiatkowski-Phillips-Schmidt-Shin test (KPSS test), introduced in Kwiatkowski et al. (1992) paper. The null of the test corresponds to stationarity of a series, the alternative to its nonstationarity. Distribution of the test statistics is nonstandard, asymptotically converges to Brownian bridges as was shown in original paper. The authors produced tables of critical values based on asymptotic approximation. Here we present results of simulation experiment aimed at studying small sample properties of the test and its empirical power.

This is a new electrochemical method for determination of lipase activity in biological fluids, including serum, plasma, and duodenal juice. Advantages of turbidimetric methods--short reaction time, and small sample and reagent volumes--are combined with those of titrimetric methods: measurement of absolute activity (i.e., no standardization required), saturated substrate conditions, and direct measurement of reaction products. The proposed method is easy, inexpensive, and takes only 3 min. Precision is good: CV = 3.74% within day and 7.3% between days at the clinical-decision concentration, CV = 1.86% within day and 4.65% between days for above-normal lipase activities. The standard curve is linear up to 4500 U/L. Results (y) correlate well with those by turbidimetry (x): y = 0.9287x - 65.3 (r = 0.9719). Reference values are between 0 and 130 U/L.

The Automated Working Memory Assessment battery was designed to assess verbal and visuospatial passive and active working memory processing in children and adolescents. The aim of this paper is to present the adaptation and validation of the AWMA battery to Argentinean Spanish-speaking children aged 6 to 11 years. Verbal subtests were adapted and pilot tested on a small sample (n = 26). A validation study was conducted including 6-, 8- and 11-year-old children (n = 210). All subtests presented an increase in difficulty as the number of to-be-remembered items raised, and showed high Cronbach's α values. Regarding validity, all subtests had medium to high and significant correlations among them, and with two external measures of working memory (Picture Span and Word Order) and an executive function task (Tower of London); correlations with Block Design were low and non-significant. We conclude that the adapted AWMA can be considered a valid and reliable battery of working memory in Argentinean Spanish-speaking children.►A high internal consistency (Cronbach's α) was observed for all AWMA tests. ►Correlations among all the tests showed they were tapping the same construct. ►Convergent and discriminant validity of the WMA were established. ►The adapted AWMA can be considered a valid and reliable battery of working memory.

Distribution of some statistics, especially rank based, with censored data are hard to get. Even if they can be worked out for small samples, they are likely to be prohibitively expensive for larger sample sizes. Therefore we need to work on the asymptotic distribution - which often works well for moderate and large sample sizes. This notes is intended to

The creep response at 600 °C of a P91 (9Cr–1Mo–NbV) steel welded joint was investigated by testing small samples from different weld locations. The microstructure of the weld was analysed by light and transmission electron microscopy. The heat-affected zone material exhibiting a fine-grained structure showed the highest minimum creep-rate values, i.e. the lowest creep strength. The coarse-grained weld metal generally had the greatest creep strength, whereas the parent metal exhibited an intermediate behaviour. The minimum creep-rate dependence on applied stress for weld metal, fine-grained heat-affected zone, and base material was described by means of the conventional power-law equation with a stress exponent close to 15. The experimental results, both in the form of strain vs. time creep curve and of minimum creep rate, were successfully used to simulate the creep response of cross-weld samples.

Text classification typically performs best with large training sets, but short texts are very common on the World Wide Web. Can we use resampling and data augmentation to construct larger texts using similar terms? Several current methods exist for working with short text that rely on using exte2rnal data and contexts, or workarounds.

Our focus is to test a new preprocessing approach that uses resampling, inspired by the bootstrap, combined with data augmentation, by treating each short text as a population and sampling similar words from a semantic space to create a longer text. We use blog post titles collected from the Technorati blog aggregator as experimental data with each title appearing in one of ten categories. We first test how well the raw short texts are classified using a variant of SVM designed specifically for short texts as well as a supervised topic model and an SVM model that uses semantic vectors as features. We then build a semantic space and augment each short text with related terms under a variety of experimental conditions. We test the classifiers on the augmented data and compare performance to the aforementioned baselines. The classifier performance on augmented test sets outperformed the baseline classifiers in most cases.