Effect of sample selection on the environmental signal derived from tree-ring series

1999 ◽  
Vol 113 (1) ◽  
pp. 83-89 ◽  
Author(s):  
Harri Mäkinen ◽  
Petteri Vanninen
2015 ◽  
Vol 3 (4) ◽  
pp. 397-406 ◽  
Author(s):  
Ronald H. Towner

AbstractDendrochronology is the most precise and accurate dating technique available to archaeologists, with resolution to the year and sometimes season. As biological specimens from human-produced contexts, dendroarchaeological samples inherently contain three kinds of information: chronological, behavioral, and environmental. The purpose of this short article is to educate archaeologists on how to avoid degrading any of these three types of information through improper sample selection, collection, preparation, or transportation techniques. Dendroarchaeology is not without limitations. First and foremost, it is dependent on the behaviors of people who built structures, made artifacts, and burned wood for fuel. If past people did not use wood, or used undateable tree species, dendrochronology will simply not be useful. In some cases, people used dateable species, but their selection criteria did not meet one of the four basic criteria necessary for successful dating. The second most important factor in successful tree-ring dating of archaeological materials is the behavior of archaeologists. Finally, preservation plays an important role in successful dating and the nature of the derived dates, but the paucity of long-lived old trees and degradation of “legacy” wood on the ground have hampered the development of millennia-long chronologies in more mesic areas.


2012 ◽  
Vol 56 (1) ◽  
pp. 5-15
Author(s):  
Mauri Timonen ◽  
Kari Mielikäinen ◽  
Samuli Helama

Abstract Tree-ring data is commonly used in forest science and dendrochronology. As the collected datasets represent restricted populations of theoretical infinite sample size, an interesting question deals with the sample selection that is carried out during the fieldwork and through the data analyses. This paper considers the latter issue, by statistically examining a recently completed Scots pine dataset of timberline tree-rings from Lapland (northern Finland). Following the detrending of individual ring-width series, the composition of the data was restricted using a pre-determined criteria of linear correlativity between the individual sample series and the master chronology (Rmaster). This procedure reduced both the number of sites and the sample size (i.e. the number of individual tree-ring series) and altered the tree-ring statistics of the remaining subset of the data in a systematic fashion. It was seen that the first-order autocorrelation, mean sensitivity and standard deviation all ascended with the uplifted Rmaster criterion. Conspicuously, such filtering also reduced the correlation between the resulting tree-ring chronology and climate parameter. The results indicated that the screening of the data will alter the chronology statistics in a way that may be artificially generated, irrelative to the predetermined sample selection criteria. We remain to assume that the most fundamental selection of data is attained through the cross-dating process.


2017 ◽  
Vol 13 (2) ◽  
pp. 142-153
Author(s):  
Ody Tegar Permana ◽  
Eliada Herwiyanti ◽  
I Wayan Mustika

This study aims to determine the effect of budgetary participation, information asymmetry, budget pressure, and organizational commitment to budgetary slack. Population in this research is all government institution in Banyumas Regency. The sample selection was conducted by census method. Dependent variable used in this research is budget slack, while the independent variable used in this research is budget participation, information asymmetry, budget pressure, and organizational commitment. The data has been collected through questionnaires, then processed with the help of SPSS software. Based on the results of multiple linear regression analysis concluded that budgetary participation, information asymmetry, and organizational commitment affect the budget slack while budget pressure has no effect. The results of this study increasingly complement previous studies in the field of management accounting, especially in the scope of budgeting.   Penelitian ini bertujuan untuk mengetahui pengaruh partisipasi anggaran, asimetri informasi, tekanan anggaran, dan komitmen organisasi terhadap senjangan anggaran. Populasi dalam penelitian ini adalah seluruh instansi pemerintahan di Kabupaten Banyumas. Pemilihan sampel dilakukan dengan metode sensus. Variabel dependen yang digunakan dalam penelitian ini adalah senjangan anggaran, sedangkan variabel independen yang digunakan dalam penelitian ini adalah partisipasi anggaran, asimetri informasi, tekanan anggaran, dan komitmen organisasi. Data yang telah dikumpulkan melalui isian kuesioner, selanjutnya diolah dengan bantuan software SPSS. Berdasarkan hasil analisis regresi linear berganda disimpulkan bahwa partisipasi anggaran, asimetri informasi, dan komitmen organisasi berpengaruh terhadap senjangan anggaran sedangkan tekanan anggaran tidak berpengaruh. Hasil penelitian ini semakin melengkapi penelitian-penelitian sebelumnya di bidang akuntansi manajemen khususnya di lingkup penganggaran.


EDUSAINS ◽  
2019 ◽  
Vol 8 (2) ◽  
pp. 201-211
Author(s):  
Yenni Kurniawati ◽  
Yuni Fatisa

Abstract Modeling and laboratory simulation can help overcome of cost obstacle, time, safety and other constraints in laboratory experiments. Many skills also had the opportunity to be fostered and promoted, especially in connection with the construction of thinking skills. However, the implementation of this program required an evaluation, in order to decided whether the program will be continuing or not, in addition its needed to found the focused of on overall quality of learning in order to make a recommendation in the decision making. This research was conducted by the mixed-method approached with triangulation design, in order to evaluate the effectiveness, problems or any obstacles of the implementation of the program. The population in this study was the third semester of pre-service chemistry students at UIN Syarif Kasim Sultan Riau, which was supported by lecturers, assistant laboratory and staf. The sample selection was done using random sampling techniques. Program evaluation in this study was conducted by the CIPP model (Context, Input, Process, Product). The results showed that the program was running quite effective when viewed from the overall average grades. The evaluation about context, inputs, processes and products had the good and very good score, in which the evaluation score of context and input, get the better score than process and product evaluation. This study recommends to be a continuing improvement program of modeling and simulation laboratories, both as an exercise before the experiments or replace the real experiments. Keywords: modeling; simulation lab; chemistry experiment Abstrak Pemodelan dan simulasi laboratorium dapat membantu mengatasi kendala biaya, waktu, alasan keselamatan dan kendala lainnya dalam praktikum di laboratorium kimia. Beragam kemampuan lain juga berkesempatan untuk ditumbuh-kembangkan terutama dalam kaitannya dengan konstruksi berfikir. Meskipun demikian, implementasi pelaksanaan program ini memerlukan evaluasi, guna memutuskan apakah program ini layak dilanjutkan ataukah tidak, selain karena diperlukannya penemuan terhadap fokus peningkatan kualitas pembelajaran secara menyeluruh guna menghasilkan rekomendasi dalam menentukan keputusan. Penelitian ini dilakukan dengan menggunakan pendekatan mixed-method desain triangulasi, guna mengevaluasi sebab-sebab efektifitas, kendala ataupun kegagalan pelaksanaan program. Populasi dalam penelitian ini adalah mahasiswa semester III jurusan Pendidikan Kimia UIN Sultan Syarif Kasim Riau, yang didukung oleh dosen, asisten laboratorium dan laboran dan pemilihan sampel dilakukan menggunakan teknik random sampling. Evaluasi program dalam penelitian ini dilakukan menggunakan model CIPP (Context, Input, Process, Product). Hasil penelitian menunjukkan bahwa program ini berjalan cukup efektif jika dilihat dari rata-rata keseluruhan nilai, mulai dari context, input, proses dan produk yang berada pada skor baik dan sangat baik, di mana skor evaluasi context dan input, lebih baik dibanding proses dan produk. Penelitian ini memberikan rekomendasi untuk terus meningkatkan penggunaan pemodelan dan simulasi laboratorium kimia, baik sebagai latihan sebelum praktikum maupun menggantikan praktikum yang sesungguhnya. Kata Kunci: pemodelan; simulasi laboratorium; praktikum kimia  Permalink/DOI: http://dx.doi.org/10.15408/es.v8i2.4394  


2015 ◽  
Vol 34 (8) ◽  
pp. 702-710
Author(s):  
Yan Lan ◽  
Rong Liang ◽  
Taijin Lu ◽  
Yong Zhu ◽  
Tianyang Zhang ◽  
...  

Author(s):  
Dariya Aleksandrovna Gavrilova ◽  
Maria Pavlovna Grushko

The aim of this work was to study peculiarities of mullet morphological organization during early ontogeny. Sample selection was made on board Caspian research and development Institute of Fisheries’ research vessel in period from June to September, 2015 in Russian waters of the Caspian Sea. Larvae aged 10 days could be characterized by heterochrony in the development of major organ systems. Nervous system and sense organs were well developed. The eyeball had all membranes well-differentiated, in the retina all the layers were formed. The olfactory fossae had cells of 3 types: olfactory receptor cells, supporting cells and basal cells. There was observed intensive formation of respiratory, cardiovascular, excretory and digestive systems. The early development of the nervous system and sensory organs of the larvae indicated adaptation of mullet to active life.


Author(s):  
Brandon M. Collins ◽  
Adrian J. Das ◽  
John J. Battles ◽  
Danny L. Fry ◽  
Kevin D. Krasnow ◽  
...  

2008 ◽  
Vol 6 (2) ◽  
Author(s):  
Iriwi Louisa S. Sinon

<p><em>Study dendrochronology or tree-ring dating is defined as the study of chronological sequence of annual growth rings in trees. Teak (Tectona grandis) is one of various tree species that has been identified for the use of tree-ring studies in tropical regions. Teak is found to be suitable for dendrochronology as it is long-lived and develops defined annual growth rings. In Java, teak cans growth naturally or intensively in plantation. The two silviculture conditions will give different sensitivity on climate effect. Therefore, the effect of silviculturer will on natural teak and plantation teak in Saradan, Madiun, and East Java. As a part of the study, ten core samples from natural- growth teak were measured. The samples of growth rings is spanned from 1832 – 2004. Using the COFECHA program, the correlation of the samples (r) was found to be 0.44 point, which is satisfactory to the standard used in dendrochronology. Thus, from this study it can be concluded that natural teak could still be used in dendrochronology, although the sensitivity are not as high as plantation teak. </em></p>


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