IDADE2
Estimating age at death of skeletal individuals

Usage

The IDADE2 web page gives you two options for estimating age in adult skeletal remains. Option 1 uses our reference data of acetabular scores collected from known-age skeletal collections using the “Rissech” (Rissech et al., 2006) and “SanMillán-Rissech” (San-Millán et al., 2017b) methods. Option 2 uses your own age-estimation scores (using any method), collected from any reference collection.

To run IDADE2-option 1, click on the button Idade2-Option 1. When you are in, first select the method and reference collection that you would like to use, select the appropriate sex, and then paste or select the test sample to estimate age at death. If you want to estimate age by using your own reference data (IDADE2-Option 2), click on the button Idade2-Option 2. When you are in, first select the file of your reference collection and then paste or select the test sample file to estimate age at death. Then press the Submit button. After the calculations, the IDADE2 web page will provide the results. See the Help section for the format input.

Results

For each individual in your sample, the following information is written on the result file: up to five characters of the individual’s identification string; estimated age at death; various measures of accuracy; and the estimating probability distribution over age classes. Open the result file in your editor to examine, edit, print, or incorporate it into other documents.

For each individual, IDADE2 calculates an age-at-death probability distribution over age classes and estimates age at death as the expected value of age at death, calculated as the sum over age classes of the center of the age class times the probability of the age class. If you include a known age for an individual, IDADE2 calculates error, a measure of accuracy for the age-at-death estimate. Error is calculated as the difference between the estimated age and the known age.

The spread of the estimating probability distribution is also described with a "confidence interval", which is a sequence of one or more consecutive age classes containing at least 95% of the distribution. The sequence is determined as follows. It includes the age class with the expected value. If the sequence does not contain 95% of the distribution, then the adjacent older age class is added if the older age classes not yet included contain more of the distribution than do the younger age classes not yet included, otherwise the adjacent younger age class is added. This process is repeated until the sequence of consecutive age classes contains at least 95% of the distribution.

For more information and an example of the output results, please visit the help tab.