scholarly journals Radiocarbon Calibration and Analysis of Stratigraphy: The OxCal Program

Radiocarbon ◽  
1995 ◽  
Vol 37 (2) ◽  
pp. 425-430 ◽  
Author(s):  
Christopher Bronk Ramsey
Keyword(s):  
Probability Distributions ◽  
Individual Case ◽  
Archaeological Sites ◽  
Radiocarbon Dates ◽  
Site Analysis ◽  
Extra Information ◽  
Dating Methods ◽  
Different Types ◽  
Types Of Information ◽  
Radiocarbon Calibration

People usually study the chronologies of archaeological sites and geological sequences using many different kinds of evidence, taking into account calibrated radiocarbon dates, other dating methods and stratigraphic information. Many individual case studies demonstrate the value of using statistical methods to combine these different types of information. I have developed a computer program, OxCal, running under Windows 3.1 (for IBM PCs), that will perform both 14C calibration and calculate what extra information can be gained from stratigraphic evidence. The program can perform automatic wiggle matches and calculate probability distributions for samples in sequences and phases. The program is written in C++ and uses Bayesian statistics and Gibbs sampling for the calculations. The program is very easy to use, both for simple calibration and complex site analysis, and will produce graphical output from virtually any printer.

scholarly journals A Time-Varying Information Measure for Tracking Dynamics of Neural Codes in a Neural Ensemble

Entropy ◽  
2020 ◽  
Vol 22 (8) ◽  
pp. 880
Author(s):  
Mohammad R. Rezaei ◽  
Milos R. Popovic ◽  
Milad Lankarany
Keyword(s):  
Kalman Filtering ◽  
Probability Distributions ◽  
Neural Code ◽  
Time Varying ◽  
Amount Of Information ◽  
Neural Ensemble ◽  
Different Types ◽  
Types Of Information ◽  
Different Time Scales ◽  
Filtering Approach

The amount of information that differentially correlated spikes in a neural ensemble carry is not the same; the information of different types of spikes is associated with different features of the stimulus. By calculating a neural ensemble’s information in response to a mixed stimulus comprising slow and fast signals, we show that the entropy of synchronous and asynchronous spikes are different, and their probability distributions are distinctively separable. We further show that these spikes carry a different amount of information. We propose a time-varying entropy (TVE) measure to track the dynamics of a neural code in an ensemble of neurons at each time bin. By applying the TVE to a multiplexed code, we show that synchronous and asynchronous spikes carry information in different time scales. Finally, a decoder based on the Kalman filtering approach is developed to reconstruct the stimulus from the spikes. We demonstrate that slow and fast features of the stimulus can be entirely reconstructed when this decoder is applied to asynchronous and synchronous spikes, respectively. The significance of this work is that the TVE can identify different types of information (for example, corresponding to synchronous and asynchronous spikes) that might simultaneously exist in a neural code.

scholarly journals Frequency Distribution of Radiocarbon Dates as a Tool for Reconstructing Environmental Changes

Radiocarbon ◽  
2007 ◽  
Vol 49 (2) ◽  
pp. 799-806 ◽  
Author(s):  
Danuta J Michczyńska ◽  
Adam Michczyński ◽  
Anna Pazdur
Keyword(s):  
Environmental Changes ◽  
Environmental Variability ◽  
Probability Distributions ◽  
Probability Density Functions ◽  
Radiocarbon Dates ◽  
The Past ◽  
Large Sets ◽  
Laboratory Calibration ◽  
Different Types ◽  
Calibration Program

Large sets of radiocarbon dates of 1019 peat, 155 speleothem, and 100 tufa samples, as well as dates of 330 fluvial samples, were investigated in order to estimate environmental variability during the last 16,000 calendar years in Poland. All 14C dating was carried out in the Gliwice Radiocarbon Laboratory, and results are stored in the RoS database. Probability density functions (PDFs) were created by summing up (on the calendar timescale) individual age probability distributions of all dates for different types of material and for different regions of Poland. We used an updated version of the Gliwice Radiocarbon Laboratory calibration program GdCALIB. The 14C dates were calibrated using the IntCal04 calibration curve (Reimer et al. 2004), and results were compared with other paleoenvironmental records. The authors conclude that analyzing PDFs of different types of sediments can be helpful in the qualitative reconstruction of the past environment. The PDF for peat samples primarily reflects paleohydrological conditions; the PDFs for speleothem and tufa samples reflect changes in temperature and humidity, while analysis of the PDF created for fluvial data is in a general agreement with the PDFs constructed for peat samples.

scholarly journals Population Dynamics and Human Strategies in Northwestern Patagonia

2021 ◽  
Vol 48 ◽  
pp. 2-21
Author(s):  
Gustavo Neme ◽  
Marcelo Zárate ◽  
María de la Paz Pompei ◽  
Fernando Franchetti ◽  
Adolfo Gil ◽  
...  
Keyword(s):  
Late Holocene ◽  
New Technologies ◽  
Probability Distributions ◽  
Archaeological Sites ◽  
Human Populations ◽  
Human Occupation ◽  
Stratigraphic Sequence ◽  
Radiocarbon Dates ◽  
Middle Holocene

In this paper we evaluate the role of human strategies in the Andean Piedmont from northern Patagonia across the Holocene. Specifically, we present the analysis of the Early Holocene-Late Holocene archaeological record of Salamanca cave (Mendoza-Argentina). We identified technological changes that occurred during the Late Holocene and the implications of a human occupation hiatus in the Middle Holocene. We follow a multiproxy approach by the analysis of radiocarbon dates, archaeofaunal remains, ceramic, lithics and XRF obsidian sourcing. We also discuss a detailed stratigraphic sequence by geomorphological descriptions, the construction of a radiocarbon sequence model and summed probability distributions, compared with other archaeological sites in the region. We conclude that after the Middle Holocene archaeological hiatus, human populations grew while guanaco populations dropped. The imbalance between demography and resources boosted the incorporation of new technologies such as ceramics and the bow and arrow, allowing people to exploit lower-ranked resources.

Effect of sleep on memory for binding different types of visual information

2020 ◽  
Author(s):  
John J Shaw ◽  
Zhisen Urgolites ◽  
Padraic Monaghan
Keyword(s):  
Visual Information ◽  
Storage Capacity ◽  
Declarative Memory ◽  
Recognition Task ◽  
Forced Choice ◽  
Long Term Memory ◽  
Term Memory ◽  
Different Types ◽  
Types Of Information

Visual long-term memory has a large and detailed storage capacity for individual scenes, objects, and actions. However, memory for combinations of actions and scenes is poorer, suggesting difficulty in binding this information together. Sleep can enhance declarative memory of information, but whether sleep can also boost memory for binding information and whether the effect is general across different types of information is not yet known. Experiments 1 to 3 tested effects of sleep on binding actions and scenes, and Experiments 4 and 5 tested binding of objects and scenes. Participants viewed composites and were tested 12-hours later after a delay consisting of sleep (9pm-9am) or wake (9am-9pm), on an alternative forced choice recognition task. For action-scene composites, memory was relatively poor with no significant effect of sleep. For object-scene composites sleep did improve memory. Sleep can promote binding in memory, depending on the type of information to be combined.

scholarly journals How the Multiplicity of Suggested Information Affects the Behavior of a User in a Recommender System

Electronics ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 741
Author(s):  
Yuseok Ban ◽  
Kyungjae Lee
Keyword(s):  
High Precision ◽  
Recommender System ◽  
Visual Information ◽  
Experimental Results ◽  
Supplementary Information ◽  
Digital Platform ◽  
Different Types ◽  
Types Of Information

Many researchers have suggested improving the retention of a user in the digital platform using a recommender system. Recent studies show that there are many potential ways to assist users to find interesting items, other than high-precision rating predictions. In this paper, we study how the diverse types of information suggested to a user can influence their behavior. The types have been divided into visual information, evaluative information, categorial information, and narrational information. Based on our experimental results, we analyze how different types of supplementary information affect the performance of a recommender in terms of encouraging users to click more items or spend more time in the digital platform.

scholarly journals The Effects of Task Complexity on the Use of Different Types of Information in a Search Assistance Tool

2020 ◽  
Vol 38 (1) ◽  
pp. 1-28 ◽  
Author(s):  
Bogeum Choi ◽  
Austin Ward ◽  
Yuan Li ◽  
Jaime Arguello ◽  
Robert Capra
Keyword(s):  
Task Complexity ◽  
Different Types ◽  
Types Of Information ◽  
Assistance Tool

Points in Time: Direct Radiocarbon Dates on Great Basin Projectile Points

2013 ◽  
Vol 78 (3) ◽  
pp. 580-594 ◽  
Author(s):  
Geoffrey M. Smith ◽  
Pat Barker ◽  
Eugene M. Hattori ◽  
Anan Raymond ◽  
Ted Goebel
Keyword(s):  
Great Basin ◽  
Archaeological Sites ◽  
Projectile Point ◽  
Radiocarbon Dates ◽  
Projectile Points ◽  
Primary Means ◽  
Point Types ◽  
Cross Dating ◽  
Age Estimates

AbstractTypological cross-dating is the primary means by which archaeological sites are placed into chronological frameworks. This approach relies on the assumption that artifacts at undated sites—usually projectile points—are coeval with similar artifacts found at Other, dated sites. While typological cross-dating is necessary in regions dominated by open-air lithic scatters, the approach can be problematic when undated and dated sites are separated by significant distances. Here, we present radiocarbon dates on projectile points with organic hafting material still attached or found within organic storage bags. Our results provide unequivocal ages for various morphological projectile point types at several Great Basin locales and should be useful to researchers seeking local age estimates for those point types, which often involves relying on chronological data from more distant sites. The results also highlight potential issues with uncritically applying typological cross-dating using typologies based on metric attributes, and in two cases, suggest the need to revise the age ranges for certain point styles in the western Great Basin.

scholarly journals The Culture of the Sakas of Semirechye: Contemporary State and Current Issues of Study

2021 ◽  
Vol 20 (3) ◽  
pp. 22-35
Author(s):  
Ernar A. Estemesov
Keyword(s):  
Iron Age ◽  
Social Groups ◽  
Archaeological Sites ◽  
Radiocarbon Dates ◽  
Funeral Rites ◽  
The Third ◽  
Urgent Task ◽  
Wide Range ◽  
Burial Mounds ◽  
Second Category

Purpose. The article describes the history and analysis of the main issues in the study of archaeological sites of the Saka period in Semirechye. They are presented by three main types on this territory: burial and memorial complexes, settlements and hoards. The first type of monuments includes numerous burial mounds, where the elite burials of “royal” type and ordinary burials are located. Both social groups are combined by the unity of funeral rites, and the main differences are the complexity of architecture, memorial practices, and richness of burial equipment in the “royal” type burial mounds. The second category of monuments is presented by the settlements that are mostly small in size. The constructions like half dugouts were discovered on them, which gave a rich ceramic material. The third type of monuments of the Saka period in Semirechye includes numerous hoards of bronze items. Some of them are represented by the cult objects (sacrificial tables, lamps and cauldrons) that mark the places of worship. A significant percentage of the hoards contain items of weapons, horse equipment and household purposes and, apparently, serve as offerings to the spirits. However, despite the considerable progress in the study of the Saka monuments of the Semirechye Region, the main problem is their cultural attribution at this time. Some researchers suggest that the independent Saka archaeological culture was formed and developed on the territory of Semirechye in the Early Iron Age, while others believe that the Saka monuments of this region belong to the broader historical and cultural community that also covers the neighboring regions of Kyrgyzstan and Xinjiang. Results Another important issue in the study of the Saka sites of Semirechye is to clarify the chronology of burial and memorial complexes. Up to now, the significant database of radiocarbon dates has been accumulated, which allows us to consider the chronological positions of a wide range of monuments in a new way. It was of great importance to obtain such dates from several burials of Karatuma necropolis, which showed that it belonged to the Saka period, since burial monuments of this appearance are traditionally dated back to the Wusun period. Conclusion. The necessity of solution of these problems is an urgent task for further research of burial and settlement objects of the Saka period in this region.

scholarly journals Examining the Effects of Message Framing and Social Norms on Judgments of Earthquake Legislation

2021 ◽  
Author(s):  
◽  
Lauren Vinnell
Keyword(s):  
Risk Perceptions ◽  
Social Norm ◽  
Message Framing ◽  
Journal Article ◽  
Psychological Research ◽  
Risk Tolerance ◽  
Earthquake Risk ◽  
Injunctive Norms ◽  
Different Types ◽  
Types Of Information

<p>To increase earthquake preparation, it is beneficial to understand the effects of different types of information used in risk communications. This thesis adapts methods that have been used with other hazards or in hypothetical situations and applies them to increasing support for current earthquake-strengthening legislation in Wellington, New Zealand (NZ). Study 1 examined valence and numerical format framing. Expressing the number of buildings affected by the legislation as a negatively-valenced frequency was found to be most effective at increasing earthquake-related judgments¹. Study 2 examined descriptive and injunctive norms and found that a range of subject factors such as age and previous knowledge of the legislation influenced the effects of norms. Study 3 used the same manipulation and included a sample from Palmerston North, where earthquake risk perceptions are lower. This study showed several clear norm effects, with the combination of both descriptive and injunctive norms the most effective at increasing support for the earthquake legislation. All three studies showed that belief in the effectiveness of strengthening earthquake-prone buildings predicted support for the legislation and lower earthquake-risk tolerance, suggesting that this could be a key perception to target in communications. Overall, these studies suggest that certain messages are more effective at increasing support for the governmental legislation, but also that framing and social norm effects on real-world issues interact with other variables such as age and knowledge which ought to be examined further to increase the usefulness of psychological research to risk communication.  ¹ The results of this study have been accepted for publication as a peer-reviewed journal article: Vinnell, L. J., McClure, J., & Milfont, T. L. (in press). Do framing messages increase support for earthquake legislation? Disaster Prevention and Management, 26(1).</p>

NEW RADIOCARBON DATES FROM ARCHAEOLOGICAL SITES IN PARTS OF IGBOLAND, SOUTHEASTERN NIGERIA

Radiocarbon ◽  
2022 ◽  
pp. 1-16
Author(s):  
Kenechukwu Chidiogo Daniel ◽  
Anselm Maduabuchi Ibeanu ◽  
Jacinta Uchenna Ikegwu ◽  
Emuobosa Akpo Orijemie
Keyword(s):  
Archaeological Sites ◽  
Human Settlement ◽  
Human Occupation ◽  
Southeastern Nigeria ◽  
Radiocarbon Dates ◽  
Iron Smelting ◽  
Subsistence Patterns ◽  
Early Human

ABSTRACT This paper presents new results of radiocarbon (14C) ages from archaeological sites in northern Igboland. The study was designed to shed more light on early human occupation and activities in the study area based on sediments from cave and iron-smelting sites. The approach consisted of ethnographic, archaeological, palynological, and slag analyses; these were complemented with 14C dates. The technology adopted as well as the paleoenvironmental conditions that prevailed during the period of human settlement in both sites was revealed. These data, complemented by 14C dates, highlight the human behavioral and subsistence patterns within the region and are comparable to those from similar sites in southeastern Nigeria.

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