Статті в журналах: "Stage sampling Design"

1

Skinner, C. J. "Design Effects of Two-Stage Sampling." Journal of the Royal Statistical Society: Series B (Methodological) 48, no. 1 (September 1986): 89–99. http://dx.doi.org/10.1111/j.2517-6161.1986.tb01393.x.

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2

Ugwu, Michael C., and Mbanefo S. Madukaife. "Two-stage cluster sampling with unequal probability sampling in the first stage and ranked set sampling in the second stage." Statistics in Transition New Series 23, no. 3 (September 1, 2022): 199–214. http://dx.doi.org/10.2478/stattrans-2022-0038.

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Abstract In this research work we introduce a new sampling design, namely a two-stage cluster sampling, where probability proportional to size with replacement is used in the first stage unit and ranked set sampling in the second in order to address the issue of marked variability in the sizes of population units concerned with first stage sampling. We obtained an unbiased estimator of the population mean and total, as well as the variance of the mean estimator. We calculated the relative efficiency of the new sampling design to the two-stage cluster sampling with simple random sampling in the first stage and ranked set sampling in the second stage. The results demonstrated that the new sampling design is more efficient than the competing design when a significant variation is observed in the first stage units.

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3

Rodrigues, Josemar. "Asymptotically design-unbiased predictors for two-stage sampling." Statistics & Probability Letters 17, no. 5 (August 1993): 411–14. http://dx.doi.org/10.1016/0167-7152(93)90263-i.

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4

Vasconcellos, Mauricio Teixeira Leite de, Pedro Luis do Nascimento Silva, and Célia Landmann Szwarcwald. "Sampling design for the World Health Survey in Brazil." Cadernos de Saúde Pública 21, suppl 1 (2005): S89—S99. http://dx.doi.org/10.1590/s0102-311x2005000700010.

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This paper describes the sample design used in the Brazilian application of the World Health Survey. The sample was selected in three stages. First, the census tracts were allocated in six strata defined by their urban/rural situation and population groups of the municipalities (counties). The tracts were selected using probabilities proportional to the respective number of households. In the second stage, households were selected with equiprobability using an inverse sample design to ensure 20 households interviewed per tract. In the last stage, one adult (18 years or older) per household was selected with equiprobability to answer the majority of the questionnaire. Sample weights were based on the inverse of the inclusion probabilities in the sample. To reduce bias in regional estimates, a household weighting calibration procedure was used to reduce sample bias in relation to income, sex, and age group.

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5

Hossaini, Mostafa, and Abdolhamid Rezaei Roknabadi. "Estimation of Subpopulation Parameters in One-stage Cluster Sampling Design." Journal of the Iranian Statistical Society 20, no. 2 (December 1, 2021): 65–78. http://dx.doi.org/10.52547/jirss.20.2.65.

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6

Raju, C., and R. Vidya. "DESIGN OF TWO-STAGE CHAIN SAMPLING PLANS WITH KULLBACK-LEIBLER INFORMATION." Advances and Applications in Statistics 73 (January 10, 2022): 47–74. http://dx.doi.org/10.17654/0972361722010.

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7

Fan, Xiang Ning, Hao Zheng, Yu Tao Sun, and Xiang Yan. "Design and Implementation of a 12-Bit 100MS/s ADC." Applied Mechanics and Materials 229-231 (November 2012): 1507–10. http://dx.doi.org/10.4028/www.scientific.net/amm.229-231.1507.

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In this paper, a 12-bit 100MS/s pipelined ADC is designed. Capacitance flip-around structure is used in sample and hold circuit, and bootstrap structure is adopted in sampling switch which has high linearity. Progressively decreasing technology is used to reduce power consumption and circuit area, where 2.5bit/stage structure is used in the first two stages, 1.5bit/stage structure is used for 3rd to 8th stages, and at the end of the circuit is a 2bit-flash ADC. Digital calibration is designed to eliminate the offset of comparators. Switched-capacitor dynamic comparator structure is used to further reduce the power consumption. The ADC is implemented by using TSMC 0.18m CMOS process with die area be 1.23mm×2.3mm. SNDR and SFDR are 65dB and 71.3dB, when sampling at 100MHz sampling clock. The current of the circuit is 96mA under 1.8V power supply.

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8

Valliant, Richard, Jill A. Dever, and Frauke Kreuter. "Effects of Cluster Sizes on Variance Components in Two-Stage Sampling." Journal of Official Statistics 31, no. 4 (December 1, 2015): 763–82. http://dx.doi.org/10.1515/jos-2015-0044.

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Abstract Determining sample sizes in multistage samples requires variance components for each stage of selection. The relative sizes of the variance components in a cluster sample are dramatically affected by how much the clusters vary in size, by the type of sample design, and by the form of estimator used. Measures of the homogeneity of survey variables within clusters are related to the variance components and affect the numbers of sample units that should be selected at each stage to achieve the desired precision levels. Measures of homogeneity can be estimated using standard software for random-effects models but the model-based intracluster correlations may need to be transformed to be appropriate for use with the sample design. We illustrate these points and implications for sample size calculation for two-stage sample designs using a realistic population derived from household surveys and the decennial census in the U.S.

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9

Hsu, Lie-Fern, and Jia-Tzer Hsu. "Economic Design of Acceptance Sampling Plans in a Two-Stage Supply Chain." Advances in Decision Sciences 2012 (February 29, 2012): 1–14. http://dx.doi.org/10.1155/2012/359082.

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Supply Chain Management, which is concerned with material and information flows between facilities and the final customers, has been considered the most popular operations strategy for improving organizational competitiveness nowadays. With the advanced development of computer technology, it is getting easier to derive an acceptance sampling plan satisfying both the producer's and consumer's quality and risk requirements. However, all the available QC tables and computer software determine the sampling plan on a noneconomic basis. In this paper, we design an economic model to determine the optimal sampling plan in a two-stage supply chain that minimizes the producer's and the consumer's total quality cost while satisfying both the producer's and consumer's quality and risk requirements. Numerical examples show that the optimal sampling plan is quite sensitive to the producer's product quality. The product's inspection, internal failure, and postsale failure costs also have an effect on the optimal sampling plan.

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10

Chen, Sixia, David Haziza, and Zeinab Mashreghi. "A Comparison of Existing Bootstrap Algorithms for Multi-Stage Sampling Designs." Stats 5, no. 2 (June 6, 2022): 521–37. http://dx.doi.org/10.3390/stats5020031.

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Multi-stage sampling designs are often used in household surveys because a sampling frame of elements may not be available or for cost considerations when data collection involves face-to-face interviews. In this context, variance estimation is a complex task as it relies on the availability of second-order inclusion probabilities at each stage. To cope with this issue, several bootstrap algorithms have been proposed in the literature in the context of a two-stage sampling design. In this paper, we describe some of these algorithms and compare them empirically in terms of bias, stability, and coverage probability.

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11

Yasmeen, Uzma, Muhammad Noor-ul-Amin, and Muhammad Hanif. "Variance estimation in stratified adaptive cluster sampling." Statistics in Transition New Series 23, no. 1 (March 1, 2022): 173–84. http://dx.doi.org/10.2478/stattrans-2022-0010.

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Abstract In many sampling surveys, the use of auxiliary information at either the design or estimation stage, or at both these stages is usual practice. Auxiliary information is commonly used to obtain improved designs and to achieve a high level of precision in the estimation of population density. Adaptive cluster sampling (ACS) was proposed to observe rare units with the purpose of obtaining highly precise estimations of rare and specially clustered populations in terms of least variances of the estimators. This sampling design proved to be more precise than its more conventional counterparts, including simple random sampling (SRS), stratified sampling, etc. In this paper, a generalised estimator is anticipated for a finite population variance with the use of information of an auxiliary variable under stratified adaptive cluster sampling (SACS). The bias and mean square error expressions of the recommended estimators are derived up to the first degree of approximation. A simulation study showed that the proposed estimators have the least estimated mean square error under the SACS technique in comparison to variance estimators in stratified sampling.

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12

Brown, Jennifer A., Mohammad Salehi M., Mohammad Moradi, Gavin Bell, and David R. Smith. "An adaptive two-stage sequential design for sampling rare and clustered populations." Population Ecology 50, no. 3 (May 21, 2008): 239–45. http://dx.doi.org/10.1007/s10144-008-0089-1.

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13

Kennedy-Shaffer, Lee, Xueting Qiu, and William P. Hanage. "Snowball Sampling Study Design for Serosurveys Early in Disease Outbreaks." American Journal of Epidemiology 190, no. 9 (April 8, 2021): 1918–27. http://dx.doi.org/10.1093/aje/kwab098.

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Abstract Serological surveys can provide evidence of cases that were not previously detected, depict the spectrum of disease severity, and estimate the proportion of asymptomatic infections. To capture these parameters, survey sample sizes may need to be very large, especially when the overall infection rate is still low. Therefore, we propose the use of “snowball sampling” to enrich serological surveys by testing contacts of infected persons identified in the early stages of an outbreak. For future emerging pandemics, this observational study sampling design can answer many key questions, such as estimation of the asymptomatic proportion of all infected cases, the probability of a given clinical presentation for a seropositive individual, or the association between characteristics of either the host or the infection and seropositivity among contacts of index individuals. We provide examples, in the context of the coronavirus disease 2019 (COVID-19) pandemic, of studies and analysis methods that use a snowball sample and perform a simulation study that demonstrates scenarios where snowball sampling can answer these questions more efficiently than other sampling schemes. We hope such study designs can be applied to provide valuable information to slow the present pandemic as it enters its next stage and in early stages of future pandemics.

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14

Puerta, Patricia, Lorenzo Ciannelli, and Bethany Johnson. "A simulation framework for evaluating multi-stage sampling designs in populations with spatially structured traits." PeerJ 7 (February 25, 2019): e6471. http://dx.doi.org/10.7717/peerj.6471.

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Selecting an appropriate and efficient sampling strategy in biological surveys is a major concern in ecological research, particularly when the population abundance and individual traits of the sampled population are highly structured over space. Multi-stage sampling designs typically present sampling sites as primary units. However, to collect trait data, such as age or maturity, only a sub-sample of individuals collected in the sampling site is retained. Therefore, not only the sampling design, but also the sub-sampling strategy can have a major impact on important population estimates, commonly used as reference points for management and conservation. We developed a simulation framework to evaluate sub-sampling strategies from multi-stage biological surveys. Specifically, we compare quantitatively precision and bias of the population estimates obtained using two common but contrasting sub-sampling strategies: the random and the stratified designs. The sub-sampling strategy evaluation was applied to age data collection of a virtual fish population that has the same statistical and biological characteristics of the Eastern Bering Sea population of Pacific cod. The simulation scheme allowed us to incorporate contributions of several sources of error and to analyze the sensitivity of the different strategies in the population estimates. We found that, on average across all scenarios tested, the main differences between sub-sampling designs arise from the inability of the stratified design to reproduce spatial patterns of the individual traits. However, differences between the sub-sampling strategies in other population estimates may be small, particularly when large sub-sample sizes are used. On isolated scenarios (representative of specific environmental or demographic conditions), the random sub-sampling provided better precision in all population estimates analyzed. The sensitivity analysis revealed the important contribution of spatial autocorrelation in the error of population trait estimates, regardless of the sub-sampling design. This framework will be a useful tool for monitoring and assessment of natural populations with spatially structured traits in multi-stage sampling designs.

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15

Crone, Paul R. "Sampling design and statistical considerations for the commercial groundfish fishery of Oregon." Canadian Journal of Fisheries and Aquatic Sciences 52, no. 4 (April 1, 1995): 716–32. http://dx.doi.org/10.1139/f95-072.

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Fisheries management is often based on data collected through various sample survey programs. At a minimum, commercial fisheries must be monitored to determine the species and age compositions of the landings; this provides the baseline data on which to assess the stocks. An equally important objective, which is often ignored, is the determination of the variability associated with derived estimates. This paper presents measures of dispersion for landing estimates generated from a two-stage sampling design used for commercially harvested groundfish species landed at Oregon ports; particular attention is given to the relative magnitudes of variability at the first and second stages of sampling designs used for estimating species and age compositions. At least two-thirds of the total amount of rockfish landed in each port/quarter stratum consisted of estimates of species composition that had small coefficients of variation (CV < 10%). For each species sampled for age composition, at least three-fourths of the total landings included estimates for individual ages with CVs < 25%. For the majority of the landings, the variation at the first stage of sampling contributed at least 63 and 90% to the variance of the estimates for the species and age compositions, respectively.

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16

Schweigert, J. F., C. W. Haegele, and M. Stocker. "Optimizing Sampling Design for Herring Spawn Surveys in the Strait of Georgia, B.C." Canadian Journal of Fisheries and Aquatic Sciences 42, no. 11 (November 1, 1985): 1806–14. http://dx.doi.org/10.1139/f85-226.

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Three estimators for two-stage sampling designs assuming unequal sized primaries (transects) were compared. The ratio estimator was found to provide the most consistent estimates of the mean and variance and so was used for estimating optimal sample design. Preliminary results from some biased sampling during 1976 and 1978 provided guidelines for the 1981 study designed to derive an optimal sampling design. Inconsistent results from the two areas surveyed during 1981 prevented general conclusions, but a corroborating resurvey of one area in 1983 suggested that a sampling intensity of five samples per 100 m of transect and transects every 250–400 m along the length of the spawn should result in estimates of the mean egg density with a standard error no greater than 25%. Systematic sampling is logistically preferable to random sampling and can be incorporated into the two-stage design described herein which should be used in future spawn surveys designed to estimate spawning escapement.

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17

Redman, Charles L. "Surface Collection, Sampling, and Research Design: A Retrospective." American Antiquity 52, no. 2 (April 1987): 249–65. http://dx.doi.org/10.2307/281779.

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Probability sampling, controlled surface collecting, and explicit research designs are standard working procedures for a large portion of the archaeological profession. The need for adopting these approaches and their utility in the field have been persuasively argued in the literature for 20 years. Despite their agreed-upon utility, these approaches are often poorly understood. Field strategies of four projects and their rationales are presented to provide examples of specific approaches that have had positive results. Based on these case studies and a review of the literature, I propose six basic principles as guides to the formulation of future field strategies. The researcher must define interpretive objectives, specify minimal data requirements, understand the problems of data recognition, structure the flow of research and evaluation, choose appropriate tools for each stage of research, and maintain cost effectiveness.

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18

Molloy, Kevin, Laurent Denarie, Marc Vaisset, Thierry Siméon, and Juan Cortés. "Simultaneous system design and path planning: A sampling-based algorithm." International Journal of Robotics Research 38, no. 2-3 (July 9, 2018): 375–87. http://dx.doi.org/10.1177/0278364918783054.

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This paper addresses the simultaneous design and path-planning problem, in which features associated to the bodies of a mobile system must be selected to find the best design that optimizes its motion between two given configurations. Solving individual path-planning problems for all possible designs and selecting the best result would be straightforward only for very simple cases. We propose a more efficient approach that combines discrete (design) and continuous (path) optimization in a single stage. It builds on an extension of a sampling-based algorithm, which simultaneously explores the configuration-space costmap of all possible designs, aiming to find the best path-design pair. The algorithm filters out unsuitable designs during the path search, which breaks down the combinatorial explosion. Illustrative results are presented for relatively simple (academic) robotic examples, showing that even in these simple cases, the computational cost can be reduced by two orders of magnitude with respect to the naïve approach. A preliminary application to challenging problems in computational biology related to protein design is also discussed.

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19

Molefe, Wilford. "Optimal allocation for equal probability two-stage design." Statistics in Transition New Series 23, no. 4 (December 1, 2022): 129–48. http://dx.doi.org/10.2478/stattrans-2022-0046.

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Abstract This paper develops optimal designs when it is not feasible for every cluster to be represented in a sample as in stratified design, by assuming equal probability two-stage sampling where clusters are small areas. The paper develops allocation methods for two-stage sample surveys where small-area estimates are a priority. We seek efficient allocations where the aim is to minimize the linear combination of the mean squared errors of composite small area estimators and of an estimator of the overall mean. We suggest some alternative allocations with a view to minimizing the same objective. Several alternatives, including the area-only stratified design, are found to perform nearly as well as the optimal allocation but with better practical properties. Designs are evaluated numerically using Switzerland canton data as well as Botswana administrative districts data.

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20

Pramod Kumar Moury , Tauqueer Ahmad, Pramod Kumar Moury ,. Tauqueer Ahmad. "Estimation of Cotton Yield at Tehsil Level using Double Sampling Approach under Stratified Two Stage Sampling Design Framework." International Journal of Agricultural Science and Research 7, no. 5 (2017): 249–56. http://dx.doi.org/10.24247/ijasroct201730.

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21

Mwangi, Jesse Wachira, and Mohamed Esha Salim. "Efficiency of Two-Stage Adaptive Cluster Sampling Design in Estimating Fringe-Eared Oryx." Open Journal of Statistics 02, no. 05 (2012): 474–77. http://dx.doi.org/10.4236/ojs.2012.25060.

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22

Chakrabarty, Tapan Kr, B. M. Singh, and T. P. Tripathi. "Estimation of Finite Population Transition Probability Matrix Based on Two Stage Sampling Design." Calcutta Statistical Association Bulletin 49, no. 3-4 (September 1999): 215–24. http://dx.doi.org/10.1177/0008068319990308.

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23

Porteus, Tom A., Suzanne M. Richardson, and Jonathan C. Reynolds. "The importance of survey design in distance sampling: field evaluation using domestic sheep." Wildlife Research 38, no. 3 (2011): 221. http://dx.doi.org/10.1071/wr10234.

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Context Sampling methods to estimate animal density require good survey design to ensure assumptions are met and sampling is representative of the survey area. Management decisions are often made based on these estimates. However, without knowledge of true population size it is not possible for wildlife biologists to evaluate how biased the estimates can be if survey design is compromised. Aims Our aims were to use distance sampling to estimate population size for domestic sheep free-ranging within large enclosed areas of hill country and, by comparing estimates against actual numbers, examine how bias and precision are impaired when survey design is compromised. Methods We used both line and point transect sampling to derive estimates of density for sheep on four farms in upland England. In Stage I we used limited effort and different transect types to compromise survey design. In Stage II we increased effort in an attempt to improve on the Stage I estimates. We also examined the influence of a walking observer on sheep behaviour to assess compliance with distance sampling assumptions and to improve the fit of models to the data. Key results Our results show that distance sampling can lead to biased and imprecise density estimates if survey design is poor, particularly when sampling high density and mobile species that respond to observer presence. In Stage I, walked line transects were least biased; point transects were most biased. Increased effort in Stage II reduced the bias in walked line transect estimates. For all estimates, the actual density was within the derived 95% confidence intervals, but some of these spanned a range of over 100 sheep per km2. Conclusions Using a population of known size, we showed that survey design is vitally important in achieving unbiased and precise density estimation using distance sampling. Adequate transect replication reduced the bias considerably within a compromised survey design. Implications Management decisions based on poorly designed surveys must be made with an appropriate understanding of estimate uncertainty. Failure to do this may lead to ineffective management.

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24

Chaudhuri, Arijit. "Estimation from an Under-Covered Sample in a Complex Survey for Auditing." Calcutta Statistical Association Bulletin 54, no. 1-2 (March 2003): 115–20. http://dx.doi.org/10.1177/0008068320030110.

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We encounter a practical problem when from a finite population a complex survey design justifies selection of a sample in five stages. The design stipulates selecting a specified number of n(> 2) first stage units by Rao, Hartley and Cochran's (RHC, 1962) scheme followed by simple random sampling (SRS) without replacement (WOR) in each of the four subsequent stages. At the implementation stage a resource crunch calls for reducing the first stage sample size from n to m ( m < n). The consequential modifications in the methods of estimation of population total, mean and ratio of two totals and those of the variance of the first and the mean square errors of the latter two estimators are spelt out. The problem arises in the context of designing audits of Government documents by appropriate sampling.

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25

Mukhopadhyay, Nitis, Mun S. Son, and Yong C. Ko. "A new two-stage sampling design for estimating the maximum average time to flower." Journal of Agricultural, Biological, and Environmental Statistics 9, no. 4 (December 2004): 479–99. http://dx.doi.org/10.1198/108571104x16196.

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26

Zhou, Haibo, Rui Song, Yuanshan Wu, and Jing Qin. "Statistical Inference for a Two-Stage Outcome-Dependent Sampling Design with a Continuous Outcome." Biometrics 67, no. 1 (June 16, 2010): 194–202. http://dx.doi.org/10.1111/j.1541-0420.2010.01446.x.

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27

Zhou, H., Y. Wu, Y. Liu, and J. Cai. "Semiparametric inference for a 2-stage outcome-auxiliary-dependent sampling design with continuous outcome." Biostatistics 12, no. 3 (January 20, 2011): 521–34. http://dx.doi.org/10.1093/biostatistics/kxq080.

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28

Fallahnezhad, MS, and E. Qazvini. "A new economical scheme of acceptance sampling plan in a two-stage approach based on the maxima nomination sampling technique." Transactions of the Institute of Measurement and Control 39, no. 7 (February 15, 2016): 1097–103. http://dx.doi.org/10.1177/0142331216629203.

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An acceptance sampling plan plays a very important role in any quality assurance system. In this new economical design of acceptance sampling plan, three types of costs are included in the objective function by considering average outgoing quality limit (AOQL), average quality level (AQL) and lot tolerance percent defective (LTPD) constraints based on the maxima nomination sampling (MNS) method in a two-stage approach. The design of this sampling inspection plan involves the minimum average total inspection (ATI). The model is designed to minimize the summation of costs and the proposed MNS economical sampling plan is compared with the classical one. Practitioners can use the proposed model to decrease the total cost of inspection.

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29

Horppila, Jukka, and Heikki Peltonen. "Optimizing Sampling from Trawl Catches: Contemporaneous Multistage Sampling for Age and Length structures." Canadian Journal of Fisheries and Aquatic Sciences 49, no. 8 (August 1, 1992): 1555–59. http://dx.doi.org/10.1139/f92-172.

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The objective of this study was to find out the optimal sampling strategy for contemporaneous multistage sampling of age and length structures of trawl catches. Samples were taken from a roach (Rutilus rutilus) stock of Lake Vesijärvi, southern Finland. Two-stage sampling proved to be superior to three-stage sampling (i.e. subsamples from the trawl catches are unnecessary). Assuming that all the age and length groups are equally important, the optimal strategy is to sample 34 fish from each of 46 loads. Compared with the present scheme (500 fish from each of 10 loads), this design cuts down the total variance of the estimated proportions of different age and length groups to about one third. An age–length key was used when estimating the proportions of the age groups. The benefits of the applied age–length key were obvious. The estimates of the proportions of different age groups were more accurate than those obtained with age readings only. Increasing the fraction of age-determined fish increases the costs, diminishes the optimal number of samples, and consequently increases the variance of the estimated proportions of different groups.

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30

Salehi, Mohammad, and David R. Smith. "Adaptive two-stage inverse sampling design to estimate density, abundance, and occupancy of rare and clustered populations." PLOS ONE 16, no. 8 (August 18, 2021): e0255256. http://dx.doi.org/10.1371/journal.pone.0255256.

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Sampling rare and clustered populations is challenging because of the effort required to find rare units. Heuristically, a practitioner would prefer to discontinue sampling in areas where rare units of interest are apparently extremely sparse or absent. We take advantage of the characteristics of inverse sampling to adaptively inform practitioners when it is efficient to move on to sample new areas. We introduce Adaptive Two-stage Inverse Sampling (ATIS), which is designed to leave a selected area after observation of an a priori number of only non-rare units and to continue sampling in the area when rare units are observed. ATIS is efficient in many cases and yields more rare units than conventional sampling for a rare and clustered population. We derive unbiased estimators of population total and variance. We also introduce an easy-to-compute estimator, which is nearly as efficient as the unbiased estimator. A simulation study on a rare plant population of buttercups (Ranunculus) shows that ATIS even with the easy-to-compute estimator is more efficient than its conventional sampling counterparts and is more efficient than Two-stage Adaptive Cluster Sampling (TACS) for small and moderate final sample sizes. Additional simulations reveal that ATIS is efficient for binary data (e.g., presence or absence) whereas TACS is inefficient for binary data. The overall results indicate that ATIS is consistently efficient compared to conventional sampling and to adaptive cluster sampling in some important cases.

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31

Wang, Yujun, Yi Wang, Lixi Wan, and Zhi Jin. "Linearity Enhancement Techniques for PGA Design." Micromachines 14, no. 2 (January 31, 2023): 356. http://dx.doi.org/10.3390/mi14020356.

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This paper presents some techniques to improve the linearity of traditional resistive feedback PGAs. By utilizing the switched op-amp in the PGA, the MOS switches in the feedback resistor array can be eliminated and thus the PGA’s linearity can be improved. The PGA’s linearity is further improved with an additional capacitor, which is used for pre-charging the sampling capacitor to strengthen its capability to drive the sampling capacitor without any extra power consumption. The pre-charge technique is especially suitable for the case where the PGA drives a large sampling capacitance. Implemented in SMIC 0.18 um CMOS technology, the proposed PGA can achieve a gain of 0.5 or 1 and consumes 4.68 mW at a single 5 V supply with the switched output stage enabled. When driving a 20 pF sampling capacitor at a sampling frequency of 200 kHz, the simulation results show that the proposed PGA can give a 9 dBc improvement in SFDR of the sampled signal compared to the traditional PGA design and the SFDR can reach up to 114 dBc.

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32

Bandyopadhyay, Uttam, and Rahul Bhattacharya. "Testing Equality of Treatment Effects in a Two-stage Censored Allocation Design." Calcutta Statistical Association Bulletin 69, no. 2 (October 26, 2017): 132–49. http://dx.doi.org/10.1177/0008068317722279.

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Tests for the equality of treatment effects are developed for a two-stage sampling design with failure censoring in each stage. Depending on the results in the first stage, adaptive failure censoring is adopted in the second stage. Assuming exponential responses, tests for comparing the response distributions are obtained and some related small sample and asymptotic properties are worked out. Relevant competitor is also suggested and compared with the proposed procedure.

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Grafström, Anton, and Anna Hedström Ringvall. "Improving forest field inventories by using remote sensing data in novel sampling designs." Canadian Journal of Forest Research 43, no. 11 (November 2013): 1015–22. http://dx.doi.org/10.1139/cjfr-2013-0123.

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It is becoming more common that auxiliary information from remote sensing is available at the planning stage of a forest field inventory. Recent developments in sampling theory allows the inclusion of such information in the sampling design to obtain better samples and, hence, improve estimates of common forest attributes. We explain the methodology and evaluate the possibility of including data from airborne laser scanning in the sampling design. The novel designs that we use can select samples that are balanced on a set of auxiliary variables and (or) well spread in a set of auxiliary variables. The results from a simulation study with real data indicate that significant improvement is achieved.

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Miller, Timothy J., John R. Skalski, and James N. Ianelli. "Optimizing a stratified sampling design when faced with multiple objectives." ICES Journal of Marine Science 64, no. 1 (November 13, 2006): 97–109. http://dx.doi.org/10.1093/icesjms/fsl013.

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Abstract Miller, T. J., Skalski, J. R., and Ianelli, J. N. 2007. Optimizing a stratifield sampling design when faced with multiple objectives – ICES Journal of Marine Science, 64, 97–109. For many stratified sampling designs, the data collected are used by multiple parties with different estimation objectives. Quantitative methods to determine allocation of sampling effort to different strata to satisfy the often disparate estimation objectives are lacking. Analytical results for the sampling fractions and sample sizes for primary units within each stratum of a stratified (multi-stage) sampling design that are optimal with respect to a weighted sum of relative variances for the estimation objectives are presented. Further, an approach for assessing gains or losses for each estimation objective by changing allocation of sample sizes to each stratum is provided. As an illustration, the analytical results are applied to determine optimal observer sampling fractions (coverage rates) for the North Pacific Groundfish Observer Programme (NPGOP), for which the multiple objectives are assumed to be bycatch (seabird, marine mammal, and non-targeted fish species) and total catch, and catch-at-length and -age of targeted fish species. Simultaneously optimizing a criterion that defines the strata of the NPGOP sampling design is also considered. When observer coverage rates are allowed to be gear-specific for the NPGOP design, the optimized objective function is between 10% and 28% less than the value corresponding to current sampling for annual data (2000–2003) and 12% less when optimized over all years combined.

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Niklitschek, Mario E., and Guillermo Trincado. "A cost effective stratified two-stage sampling design to estimate the forest land area of southern Chile." Canadian Journal of Forest Research 41, no. 7 (July 2011): 1509–21. http://dx.doi.org/10.1139/x11-040.

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There is a growing demand for improving the measurement of forest resources, with more frequent updating and better information on environmental variables. We explore the cost efficiency of a stratified two-stage design using area sampling to estimate the forest plantation and native forest areas in southern Chile. Analytical expressions for the approximate mean square error of combined and separate ratio estimators are derived applying Taylor linearization. Under a unified framework, this procedure allows the evaluation of the precision of design and post-design estimators for unequal unit area sizes at both stages. Monte Carlo simulations were used to assess empirically the approximate analytical measures of the mean square error and the biases associated with the ratio estimators. Adopting proportional allocation among strata and clusters, the optimal allocation among the two stages is determined. A substantial improvement in sampling precision was achieved using the separate ratio estimator and the bias was found to be small. Post-stratification based on categorical information on growing zones also improved the precision of estimating the forest plantation area and a smaller extent the native forest area. The results of this paper support a wider adoption of sampling methods to estimate land use and land cover at regional or national levels.

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Chen, Guo Ping, Xian Zhong Jian, and Er Liang Xiao. "Design and Simulation of a Pipeline Analog-to-Digital Converter." Applied Mechanics and Materials 182-183 (June 2012): 1154–58. http://dx.doi.org/10.4028/www.scientific.net/amm.182-183.1154.

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The pipeline Analog-to-Digital Converter is highlight for its high resolution, accuracy, speed and low power consumption. In this paper, we have completed the design and simulation of a pipeline ADC with the SIMULINK toolbox of MATLAB. The model of 1.5 bit per stage was set up, and nine stages were connected to establish the system model. The system model can work correctly at 100MHz sampling frequency and reach 10 bit resolution. The simulation results can verify the correction of the pipeline ADC theory.

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Kang, Mihyun, and Paulette Hebert. "Case study of a custom colored carpet tile prototype utilizing sustainable sampling." Facilities 32, no. 3/4 (February 25, 2014): 104–19. http://dx.doi.org/10.1108/f-05-2011-0043.

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Purpose – The purpose of this study was to examine the process of a custom colored carpet prototype that utilized innovative and sustainable sampling techniques. Design/methodology/approach – This study adapted the prototype design process of problem definition and research; creative exploration; and implementation by LaBat and Solowski. The stages of problem definition and research and creative exploration were conducted for this study. Since only a sample of the carpet tile was developed, the implementation stage was not applicable and was replaced with an deliberation stage. The deliberation process for sustainable sampling was based on the five major performance categories of the sustainable carpet assessment standard, NSF/ASNI 140-2007: Public Health and Environment; Energy and Energy Efficiency; Bio-based Content, Recycled Content, and Environmentally Preferable Materials; Manufacturing; and Reclamation and End of Life Management. Findings – A third party's proprietary sustainable sampling system was employed to support experimentation with multiple colorway applications, while minimizing sample waste. A custom colored commercial carpet tile that reflects one university's unique color palette was developed in collaboration with a large carpet manufacturer. Research limitations/implications – The deliberation stage was not intended to measure or award the points for the five performance categories. Moreover, the researchers are not eligible to certify carpet products. The certifiers are reputable auditors such as Scientific Certification Systems, UL Environment and NSF International. Rather, the five major performance categories of NSF/ASNI 140-2007 were employed as the framework for discussion. Practical implications – Although creating a custom-colored commercial carpet tile product was a laborious and time-consuming activity, consumers in today's society have begun to expect tailored products that meet their needs. Custom colorization provides for personalization and the support of established color palettes without the anticipated higher associated expenses incurred with a completely custom product. At universities, where the home team's colors are omnipresent and extremely meaningful to stakeholders, developing custom colored carpet tile is appropriate. Originality/value – Sustainable sampling was effectively utilized to facilitate a custom colored carpet tile prototype. This study fills a gap in the current literature since it incorporates a case study of the design of a sustainable interior product. Previously, few studies have tracked the inception and development of a carpet product through its design phases.

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Luca, Stijn, Johan Vandercappellen, and Johan Claes. "A web-based tool to design and analyze single- and double-stage acceptance sampling plans." Quality Engineering 32, no. 1 (August 26, 2019): 58–74. http://dx.doi.org/10.1080/08982112.2019.1641207.

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Qin, G., and H. Zhou. "Partial linear inference for a 2-stage outcome-dependent sampling design with a continuous outcome." Biostatistics 12, no. 3 (December 14, 2010): 506–20. http://dx.doi.org/10.1093/biostatistics/kxq070.

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Desweni, Erin, Wirsma Arif Harahap, and Afriwardi Afriwardi. "Pemeriksaan Payudara Sendiri (SADARI) dengan Stadium Kanker Payudara." Journal of Telenursing (JOTING) 3, no. 2 (November 16, 2021): 629–35. http://dx.doi.org/10.31539/joting.v3i2.2980.

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This study aims to determine the relationship between breast self-examination (BSE) and the stage of breast cancer at RSUP Dr. M. Djamil Padang in 2020. The method used is a mixed-method with a Sequential Explanatory Design. Sampling technique using Consecutive Sampling. Quantitative data was obtained through questionnaires and qualitative data using interviews. The results showed that the number of respondents who were not good at breast self-examination (BSE) was 64 (58.2%) and respondents who were good at breast self-examination (BSE) were 46 (41.6%). The most common breast cancer stages were at stage 3 of 67 (63.9%), stage 2 of 30 (27.3%) and the least at stage 4 was 13 (11.8%) with a p-value = 0.020. In conclusion, there is a relationship between breast self-examination (BSE) and the stage of breast cancer. Keywords: Breast Self-Examination (BSE), Breast Cancer Stage

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Nicoletti, João V. M., Marcello R. A. Franchi, Anamari V. de A. Motomiya, Wagner R. Motomiya, and José P. Molin. "Efficiency and quality of soil sampling according to a sampling tool." Revista Brasileira de Engenharia Agrícola e Ambiental 27, no. 6 (June 2023): 480–86. http://dx.doi.org/10.1590/1807-1929/agriambi.v27n6p480-486.

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ABSTRACT Soil sampling is a fundamental stage for recommending agricultural correctives and fertilizers, estimating the nutritional demands of plants, and consequently maximizing productivity. Therefore, this study aimed to assess the performance of three soil samplers in different management systems in terms of sample quality and operational efficiency. A completely randomized experimental design was used in a factorial scheme. Three samplers and two sampling depths (3 × 2) were used with four replicates. At each sampling location, eight single samples were taken at a varying sampling depth of 0.0-0.2 and 0.2-0.4 m, and the collection time was recorded. Samples were analyzed for chemical attributes and granulometry. Statistically significant differences were observed for specific attributes (organic matter, K, Ca, CEC, pH, and S). In terms of operational efficiency, the hydraulic sampler was more efficient than the other samplers, being three times faster than the combustion drill and six times faster than the manual probe. Thus, it is suitable and reliable for soil sampling purposes.

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Yang, D. Aaron, and Richard A. Laven. "Design-Based Approach for Analysing Survey Data in Veterinary Research." Veterinary Sciences 8, no. 6 (June 8, 2021): 105. http://dx.doi.org/10.3390/vetsci8060105.

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Sample surveys are an essential approach used in veterinary research and investigation. A sample obtained from a well-designed sampling process along with robust data analysis can provide valuable insight into the attributes of the target population. Two approaches, design-based or model-based, can be used as inferential frameworks for analysing survey data. Compared to the model-based approach, the design-based approach is usually more straightforward and directly makes inferences about the finite target population (such as the dairy cows in a herd or dogs in a region) rather than an infinite superpopulation. In this paper, the concept of probability sampling and the design-based approach is briefly reviewed, followed by a discussion of the estimations and their justifications in the context of several different elementary sampling methods, including simple random sampling, stratified random sampling, and one-stage cluster sampling. Finally, a concrete example of a complex survey design (involving multistage sampling and stratification) is demonstrated, illustrating how finding unbiased estimators and their corresponding variance formulas for a complex survey builds on the techniques used in elementary sampling methods.

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Vasconcellos, Mauricio Teixeira Leite de, Pedro Luis do Nascimento Silva, Moyses Szklo, Maria Cristina Caetano Kuschnir, Carlos Henrique Klein, Gabriela de Azevedo Abreu, Laura Augusta Barufaldi, and Katia Vergetti Bloch. "Sampling design for the Study of Cardiovascular Risks in Adolescents (ERICA)." Cadernos de Saúde Pública 31, no. 5 (May 2015): 921–30. http://dx.doi.org/10.1590/0102-311x00043214.

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The Study of Cardiovascular Risk in Adolescents (ERICA) aims to estimate the prevalence of cardiovascular risk factors and metabolic syndrome in adolescents (12-17 years) enrolled in public and private schools of the 273 municipalities with over 100,000 inhabitants in Brazil. The study population was stratified into 32 geographical strata (27 capitals and five sets with other municipalities in each macro-region of the country) and a sample of 1,251 schools was selected with probability proportional to size. In each school three combinations of shift (morning and afternoon) and grade were selected, and within each of these combinations, one class was selected. All eligible students in the selected classes were included in the study. The design sampling weights were calculated by the product of the reciprocals of the inclusion probabilities in each sampling stage, and were later calibrated considering the projections of the numbers of adolescents enrolled in schools located in the geographical strata by sex and age.

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Sukma, Trisya Afidah, Mundilarto Mundilarto, and Nadia Darma Putri. "Local wisdom-Based Electronic Book on Newton's Law." Jurnal Ilmiah Pendidikan Fisika Al-Biruni 8, no. 2 (October 30, 2019): 197–206. http://dx.doi.org/10.24042/jipfalbiruni.v0i0.4368.

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This study aims to develop a physics e-book based on local wisdom in Newton's law. This research is research and development (R&D) using the 4D model. The stages are: define, design, development, and disseminate. The sampling technique used is the purposive sampling of 36 respondents. At the define, the stage is done with the preliminary analysis, analysis of learners, task analysis, concept analysis, and formulate learning objectives. In the design stage, the arrangement of the instrument, media and format selection, and design of the initial product. The developing stage includes the review by the supervisor, expert assessment, and product trial. The technique of collecting data uses a questionnaire. The questionnaire used in this study was divided into (1) questionnaire on teacher and student needs, (2) product feasibility questionnaire based on material experts and media experts, (3) student response questionnaires. The results of this study show that physics e-book based on local wisdom is very feasible to use in learning physics in Newton's law material. Based on the research result, learning using e-book based on local wisdom is learning media innovation that supports education in the industrial revolution 4.0 without forgetting local culture.

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Munafiah, Durrotun, Nur Laila, Tri Ismu Pujiyanto, Sa'adah Mujahidah, and Mariza Mustika Dewi. "MANFAAT HYPNOBIRTHING DAN DIFUSE AROMATHERAPY LAVENDER TERHADAP LAMA PERSALINAN KALA I DAN II." Midwifery Care Journal 3, no. 3 (July 29, 2022): 73–77. http://dx.doi.org/10.31983/micajo.v3i3.8681.

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The prolonged first and second stage of labor will cause various maternal and fetal complications. Methods for mothers to feel relaxed is the hypnobirthing relaxation method and using Lavender Aromatherapy. The aim of the study was to determine the effect of the combination of hypnobirthing and diffuse lavender aromatherapy on the duration of labor in the I and II stages. This type of research is quantitative, quasi-experimental design with posttest only control group design. The population of this study was all mothers giving birth in the Tengaran Health Center Work Area in August 2021 with a total of 20 respondents. The sample is set at 10 respondents per group. The sampling technique in this research is purposive sampling. Data analysis used univariate and bivariate analysis using independent t-test and Mann Whitney. The duration of the first stage of labor in the group that gave the combination of hypnobirthing and diffuse lavender aromatherapy had an average length of the first stage of 289.5 minutes, the median of 290 minutes, the average length of the second stage of 29 minutes, and the median of 30 minutes. The control group had an average length of the first stage of 330 minutes, a median of 340 minutes, an average length of the second stage of 38.5 minutes, a median of 40 minutes. There is an effect of the combination of hypnobirthing and diffuse aromatherapy lavender on the duration of labor in the first and second stages (0.0010.05 and 0.0060.05).

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Baquero, Oswaldo Santos, Marcos Amaku, Ricardo Augusto Dias, José Henrique Hildebrand Grisi Filho, José Soares Ferreira Neto, and Fernando Ferreira. "Validity of a two-stage cluster sampling design to estimate the total number of owned dogs." Preventive Veterinary Medicine 151 (March 2018): 40–45. http://dx.doi.org/10.1016/j.prevetmed.2017.12.017.

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Saini, Monika, and Shashi Bahl. "Estimation of Population Mean in Two Stage Design using Double Sampling for Stratification and Multiauxiliary Information." International Journal of Computer Applications 47, no. 9 (June 30, 2012): 17–21. http://dx.doi.org/10.5120/7216-0011.

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Zhou, Qingning, Jianwen Cai, and Haibo Zhou. "Semiparametric inference for a two-stage outcome-dependent sampling design with interval-censored failure time data." Lifetime Data Analysis 26, no. 1 (January 7, 2019): 85–108. http://dx.doi.org/10.1007/s10985-019-09461-5.

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Hidayah, Anisatul, Fitri Hilmiyati, and Juhji Juhji. "PENINGKATAN PEMAHAMAN IPA PESERTA DIDIK SD: SEBUAH PENGEMBANGAN BAHAN AJAR BERBASIS PENDEKATAN PEMECAHAN MASALAH." Primary : Jurnal Keilmuan dan Kependidikan Dasar 14, no. 2 (January 24, 2023): 174–90. http://dx.doi.org/10.32678/primary.v14i2.6715.

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This study aimed to produce a teaching material product as a companion book based on a feasible and practical problem-solving approach to increase students' understanding of natural sciences on forms and energy sources. Understanding the material taught to students is not fully understood, as can be seen from the acquisition scores obtained by students who are still below the minimum completeness criterion of 70. This research method is development or Research and Development adapted from the ADDIE development model, which consists of five stages, namely: 1) Analysis Phase (Analyze); 2) Design Stage (Design); 3) Development Stage; 4) Implementation Stage (Implementation); and 5) Evaluation Stage. The research subjects were class IV MIS As-Shofiah using a nonprobability sampling technique (purposive sampling) of 3 students with the provisions of the highest student learning outcomes, average scores, and lowest scores with the hope that they could represent all students in class IV A. The instruments were questionnaires and questions. The results showed that the developed teaching materials fall into the "Very Good" criteria by obtaining a score of 100% from material experts, 86% from design experts, and 98% from student responses to using advanced teaching materials. The results of teaching materials trials related to material understanding were carried out in class IV students by obtaining an average pretest score of 46.25 and an average posttest score of 90.

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Rose, Uwe, Stefan Schiel, Helmut Schröder, Martin Kleudgen, Silke Tophoven, Angela Rauch, Gabriele Freude, and Grit Müller. "The Study on Mental Health at Work: Design and sampling." Scandinavian Journal of Public Health 45, no. 6 (July 4, 2017): 584–94. http://dx.doi.org/10.1177/1403494817707123.

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Aims: The Study on Mental Health at Work (S-MGA) generates the first nationwide representative survey enabling the exploration of the relationship between working conditions, mental health and functioning. This paper describes the study design, sampling procedures and data collection, and presents a summary of the sample characteristics. Methods: S-MGA is a representative study of German employees aged 31–60 years subject to social security contributions. The sample was drawn from the employment register based on a two-stage cluster sampling procedure. Firstly, 206 municipalities were randomly selected from a pool of 12,227 municipalities in Germany. Secondly, 13,590 addresses were drawn from the selected municipalities for the purpose of conducting 4500 face-to-face interviews. The questionnaire covers psychosocial working and employment conditions, measures of mental health, work ability and functioning. Data from personal interviews were combined with employment histories from register data. Descriptive statistics of socio-demographic characteristics and logistic regressions analyses were used for comparing population, gross sample and respondents. Results: In total, 4511 face-to-face interviews were conducted. A test for sampling bias revealed that individuals in older cohorts participated more often, while individuals with an unknown educational level, residing in major cities or with a non-German ethnic background were slightly underrepresented. Conclusions: There is no indication of major deviations in characteristics between the basic population and the sample of respondents. Hence, S-MGA provides representative data for research on work and health, designed as a cohort study with plans to rerun the survey 5 years after the first assessment.

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