Showing papers by "Indian Agricultural Statistics Research Institute published in 2001"

Integrated effect of organic and inorganic manuring on yield sustainability in long-term fertiuzer experiments

Abstract: Incorporation of farmyard manure @ 10–15 t ha−1 yr−1 with recommended NPK fertilizer doses to the kharif crop in the sequence in long term fertilizer experiments of ICAR has a pronounced effect in enhancing the efficiency of chemical fertilizers. The cropwlse pooled. results over 25 years have indicated significant improvements in crop productivity with the integrated use of organic and inorganic fertilizers by 11 to 44 and 15 to 26 per tent, respectively over optimal (100% NPK) and superoptimal (150% NPK) levels of chemical fertilizers at most of the locations. Beneficial residual effect varying between 11 to 31 per cent has also been observed on the succeeding crop in the sequences in different soil groups. In addition to the sustainable yield gains, use of organic manure has also significantly increased the availability of the limiting nutrients in the soil and thus maintained the fertility of different soils.

Robustness of designed experiments against missing data

Abstract: This paper investigates the robustness of designed experiments for estimating linear functions of a subset of parameters in a general linear model against the loss of any t( U 1) observations. Necessary and sufficient conditions for robustness of a design under a homoscedastic model are derived. It is shown that a design robust under a homoscedastic model is also robust under a general heteroscedastic model with correlated observations. As a particular case, necessary and sufficient conditions are obtained for the robustness of block designs against the loss of data. Simple sufficient conditions are also provided for the binary block designs to be robust against the loss of data. Some classes of designs, robust up to three missing observations, are identified. A-efficiency of the residual design is evaluated for certain block designs for several patterns of two missing observations. The efficiency of the residual design has also been worked out when all the observations in any two blocks, not necessarily ...

Epilepsy in children with cerebral palsy.

Abstract: This article deals with the clinical profile of children with cerebral palsy and epilepsy, and to study the clinical predictors of response to anti-epileptic drugs. It is a prospective hospital based follow-up study. All the children who presented with cerebral palsy and history of seizure (other than neonatal seizures) over a period of one year were included. Seizures were classified according to ILAE classification. An EEG was obtained in all cases. Neuroimaging was done in all patients. Eighty-five patients were studied and followed for minimum of 12 months. Perinatal factors accounted for 62 (72.3%) cases. The motor deficits seen were quadriparesis (n = 64), hemiplegia (n = 12) and diplegia(n = 9). Associated mental retardation was seen in 80.9% patients with quadriparesis. A predominance of generalised epilepsy was seen with generalised tonic clonic seizures (32.9%) followed by myoclonic seizures(30.6%)and localisation related epilepsy (24.7%). The patients with quadriparesis were more likely to have generalised epilepsy and 52.4% of them required two or more anti-epileptic drugs for control of seizures. Patients with hemiplegia had localisation related epilepsy in 83.3% of cases. On multivariate analysis presence of quadriparesis, microcephaly, mental retardation and myoclonic epilesy were found to predict the poor response to AED. Epilepsy in patients with cerebral palsy is of severe nature and difficult to control. Presence of quadriparesis, mental retardation and myoclonic seizures was predictive of poor response to anti-epileptic drugs.

Small Sample Comparison of Modified Chi‐Square Test Statistics for Survey Data

Abstract: The problem of categorial data analysis in survey sampling arises because of non-independence of sample elements of the sample obtained through imposed sampling design. In this article the performance of modified X 2 statistic for testing independence of attributes have been evaluated for small sample sizes with the help of log-linear models with respect to its achieved level of significance for fixed nominal level at 5%, through simulation technique. It hase been observed that the perfiormance of these test statistics depends on average and coefficient of variation of eigen values of design effect matrix. The first order corrected statistic is able to capture the effect of sampling design to a great extent but the performance of second order corrected statistic is much better. Further, these modified X 2 test statistics were applied to a real survey data and their performance were evaluated with respect to their achievied level of significance.

Osmotic Dehydration of Banana (Dwarf Cavendish) Slices

Abstract: Osmotic dehydration Of banana slices (Dwarf Cavendish) was studied at five levels each of temperature 25°C, 35°C, 45°C, 55°C and 65°C, solution to sample ratio 1, 3, 5, 7 and 9; and concentration of sugar solution 40, 50, 60, 70 and 80° Brix. A modified second order rotatable design was adopted for three factors each at five levels. The moisture loss and sugar gain were characterized at one-hour interval for four hours. Response Surface Methodology was used.to optimize the osmotic dehydration with special reference to maximum moisture remoyal and minimum solids gain. The study indicated that about 16% of the initial moisture could be removed from the banana slices after one hour of osmosis at a sugar concentration 70° Brix, solution to sample ratio of 1.5 and a temperature of 50°C with only 5% of initial solids as sugar gain. The second order response surface model could estimate the moisture losses as well as solids gain within 5% of the observed value.

Use of expected-value parameters for estimating length-weight relationship in fishes

Abstract: Nonlinear estimation procedures are generally employed for determining the length-weight relationship in fishes. As no attention is paid to reparameterization of the parameters, the model-data set combination sometimes exhibits an extremely high nonlinear behaviour, i.e. the parameter-effects measure of curvature is very large. The purpose of the present paper is to make use of'expected-value' parameters which depict close-to-linear behaviour. The methodology is illustrated with the help of data taken from fisheries literature.