### Seriation (archaeology) - Wikipedia

an absolute date for an archaeological site, are a contribution of the physical and the below will focus on stratigraphy and seriation, dating techniques used by. Jul 27, Seriation is the first scientific dating method, invented by Using seriation at our hypothetical junkyard sites, we will try to establish the. seriations can be inferred to be chronologies, but these limits are more restricted than generally appreciated. Relative-dating methods stipulate the temporal dimension of the data by placing a given unit in applicable only to single sites.

Some design styles were used for a very long time as the shape constructed was handy and no improvement or ornament was added. Of course, these design styles are not eligible for chronological seriation. For example, knives in early medieval times in Europe are said to show no chronological variation. In addition to temporal organization, seriation results may reflect assemblage differences in social status, age, sex or those resulting from regional variation or a combination of two or more of these factors.

The result is not a chronological sequence due to the selection of types, the ordering seems to start with extremely male hoards and ends with extremely female ones. Three conditions for chronological seriation[ edit ] Doran and Hodsonp.

## Limitations of seriation dating

Regional variation must be kept to a minimum, i. The objects analyzed must all come from a single cultural tradition. The traits or attributes included in the seriation must depend on cultural aspects rather than on function. Statistical methods[ edit ] Development of seriation methods[ edit ] Nowadays, seriation results are no longer produced manually as in Petrie's times but by appropriate algorithms.

Though according to David George KendallPetrie's paper showed already a deep understanding of the mathematics of the seriation problem Quote: In Baxter'sp. Robinson based his frequency seriation method on a similarity matrix. InKendall proposed the use of multidimensional scaling techniques for seriation problems, and this approach has also been used by some other scientists see Baxterpp. Baxter also presents a review of statistical methods for seriation and a description of these approaches pp.

InDoran and Hodson pp.

Correspondence analysis for seriation purposes[ edit ] Today, the most popular seriation method both for contextual and frequency problems is based on correspondence analysis. The sequence of the first axis of a correspondence analysis is considered the best seriation order Shennan[4] p. Using this technique, not only the sequence of the objects but also those of the design styles is established.

Note that external evidence is needed to establish the direction of the sequence calculated, i. The resulting scatterplot showed the form of a horse-shoe where the graves were arranged on the curve according to their chronological order.

Similarly, a mapping of the component scores for the first two axes of the correspondence analysis result will display a parabola if the design styles considered are controlled by one factor only like chronology. This is called the arch effect by Hill and Gauch Therefore, it is recommended inspecting the scatterplot of the first two axes of correspondence analysis to find out if other factors play a role as well see Examples 2 and 3. If more than one factor is important, the arch effect may distort the results.

Hill and Gauch presented a method to remove this effect. InGroenen and Poblome adapted the correspondence analysis algorithm to combine seriation with absolute dates and stratigraphic relationships. Small contextual seriation[ edit ] The small example below was inspired by Flinders Petrie's serial ordering of Egyptian pottery as published by Renfrew and Bahnp. Raw data for contextual seriation Result of contextual seriation Another way of presenting the raw data for contextual seriation: For example, consider the first column: A beaker is contained in contexts 1 and 2.

Contextual seriation sorts the design styles and the contexts in such a way that the star symbols are found as close as possible to the diagonal of the table.

Of course, for a small examples like this, no computer programs are needed to find the best ordering, but for larger data sets like the graves studied by Petrie they are extremely helpful. Simulated data, seriation and correspondence analysis[ edit ] The data presented in this example was simulated by WinBasp.

Initially 60 contexts called units in WinBasp were created along with 50 types. The contexts were labeled in chronological order by numbers 01 to 60, the types are labeled in the form T to T If a type is represented by one object only this object is not relevant for the chronological sequence as it does not provide a link to another context.

Similarly, contexts containing one object only are irrelevant for seriation. Therefore, the contexts with one or no object and types represented by one object or not at all were eliminated. The resulting raw simulated data consisting of 43 contexts and 34 types are shown on the left. As expected, the dots indicating the occurrence of a type in a context are close to the diagonal of the table. Raw simulated data for contextual seriation Result of seriation The image on the right hand side shows the result of the seriation for this data set.

Note that the dots are even more compact along the diagonal of the table compared to the raw data. Others are simply valid alternative solutions, which point to the influence of multiple causal factors. By including all valid orders, one can use the distribution of solutions as data regarding the structure of interaction between localities, and thus evidence about past cultural transmission. Our algorithm also enables statistical assessment of the significance of solutions, given the sample sizes employed.

Using an example from the Mississippi River Valley, we demonstrate how the new algorithm provides detailed insight into the temporal and spatial structure of inheritance.

### Limitations Of Seriation Dating | ВКонтакте

Suitably extended in this way, we argue that DFS has the potential to inspire new innovative approaches to the archaeological record as much as it did in the s as a critical tool for building chronology. Materials and Methods A Short History of Seriation in Archaeology While not in common usage, seriate and seriation are English words that refer to arranging or occurring in one or more series [ 50 ].

The terms describe an archaeological method without defining it—there are many ways to order or arrange items in a series. The origins of the method are a bit opaque since variants were in used before it was given the name. Identifying its history and understanding the scope of the method, therefore, requires tracing the components involved in seriation that emerge over time and under which contemporary seriation now exists.

Sir Flinders Petrie [ 51 ] is generally credited with inventing seriation. Working with predynastic Egyptian materials, Petrie used ceramics found in graves to develop a chronology. Since the history of Egyptian ceramics must have followed some particular course and thus presented an unique sequence of ceramic type replacements, the combinations of ceramic types found in grave lots allowed him to reconstruct both the history of ceramics and arrange the grave lots in chronological order.

As in all seriation, the product was just an order; one had to determine independently usually through superposition which end of the order was most recent. Kroeber [ 52 ] is credited with stimulating the American development. Kidder and Nels C.

Nelson all of whom were conducting stratigraphic excavations in the American Southwest [ 75052 — 54 ]. As powerful as seriation proved to be, these early formulations were entirely intuitive and based on the generalization that greater temporal differences between assemblages caused larger differences between frequencies of decorated types.

The shape of the curves that led to the ability to order assemblages were not justified and even the terms used were ad hoc: Since knowledge of rates of change was impossible, all that one could say about the characteristic distributions were that they were unimodal in that they had a single peak frequency and decreased in value away from the peak in both directions.

Furthermore, there was little interest in figuring out why the characteristic distributions occurred. It was enough that they did and could be used to order assemblages.

Such statements are, of course, just descriptions of the observed frequencies and represent, moreover, the selection of simply one type of distribution that the popularity of styles can take.

Seriation thus was based on an empirical generalization about the distribution of stylistic classes through time. Almost all of the early work involved frequencies of stylistic historical pottery classes used as attributes of assemblages, the assemblages being groups of artifacts, usually but not always, pottery. By the s, use of the method had spread from the Southwest to include the Eastern United States and the Arctic and by the s even Peru and Amazonia had chronologies based on seriation [ 955 ].

Ford [ 5657 ] played a critical role in disseminating the method so widely and was the only scholar to take an interest in the theoretical aspects of seriation until the s [ 58 — 60 ].

Although Kroeber had been aware of potential problems derived from sample size effects, Ford brought these considerations to the fore, albeit in a highly intuitive, non-quantitative, and ultimately incorrect way. More importantly, he deduced a series of conditions under which the empirical generalization driving seriation might be expected to hold: Ford, like his predecessor, arrived at the final arrangement by eyeballing trial and error orderings for conformance to the unimodal distribution model.

InGeorge Brainerd and Eugene Robinson proposed an entirely new technique for arriving at the order of groups [ 4361 ].

**Seriation (archaeology)**

They devised a measure of similarity, since termed the Brainerd and Robinson Index of Agreement or simply the Brainerd and Robinson Coefficient, with which pairs of assemblages could be compared in terms of type composition.

Thus described, they noted that in correct solutions the most similar assemblages were adjacent to one another; since this order was unique, groups could be chronologically ordered simply by arranging them so that the most similar units were adjacent. Brainerd and Robinson did this by rearranging rows and columns in a square matrix each group is compared with every other group of similarity coefficients; in a perfect solution, the magnitude of the similarity coefficients would decrease uniformly monotonically away from the diagonal of the matrix the groups compared with themselves.

Cowgill [ 62 ] developed a similarity-based approach for occurrence descriptions paralleling the techniques developed by Brainerd and Robinson for frequency descriptions.

## Dating Techniques - Seriation

Thus, two kinds of seriation approaches emerged. Frequency seriation uses ratio level abundance information for historical classes [ 545657 ]. Like Ford, one could insist on an exact match with the unimodal model before regarding an order as chronological, a deterministic solution.