We use cookies to distinguish you from other users and to provide you with a better experience on our websites. Close this message to accept cookies or find out how to manage your cookie settings.
We use cookies to distinguish you from other users and to provide you with a better experience on our websites. Close this message to accept cookies or find out how to manage your cookie settings.
from PART III - ARCHAEOLOGICAL APPROACHES TO DATA
Published online by Cambridge University Press: 22 July 2017
An integral aspect of archaeological data is that they come from particular places. We often want to examine the distribution of artifacts, sites, or features over space and R provides a number of tools for this purpose. We may also be interested in the direction or orientation of the object, house, or feature. This chapter will cover some of the basics, but there are specialized R packages for mapping and for analyzing gridded and point data. If most of your analysis involves spatial data it may be easier to use a geographic information system (GIS) package, but R can handle shapefiles and other data structures that are produced by those packages and it provides extensive support for statistical analysis of spatial data. In this chapter we will cover directional statistics, creating simple distribution maps based on gridded or piece plotted data.
CIRCULAR OR DIRECTIONAL STATISTICS
Circular statistics include direction and orientation (Gaile and Burt, 1980; Jammalamadaka and Sengupta, 2001; Mardia and Jupp, 2000). If we are interested in the direction of something (for example burials or rock shelter openings), then we are using directional data. In general, this is recorded in degrees measured clockwise from north, but it can also include cyclical data where the cycle repeats daily, weekly, monthly, or yearly. In other cases, we are interested in the orientation of an elongated flake, blade, or bone fragment. Orientation can be defined as north/south or east/west so we are only using half of the circle since 0° and 180° or 90° and 270° are the same orientation. With bone fragments, for example, we usually cannot identify which end is the front and which is the back so we are working with orientation. With blades, we could define the platform end as the front in which case we could measure direction rather than orientation, but often only the orientation is recorded. The research question under consideration will help to make the decision between direction and orientation. Analytically, the first step with orientation data is to double each value and analyze it as directional data.
To save this book to your Kindle, first ensure [email protected] is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Find out more about the Kindle Personal Document Service.
To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Dropbox.
To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Google Drive.
