You can use the following sources to read about similarity coefficients Sørensen–Dice in Wikipedia, Podani 2000, Jan Schulz 2008. .The SDC includes a page Similarity and distance.
The opposite to similarity is difference. Difference can be measured as Euclidean distance in feature space. If the features used for measuring Euclidean distance are spatial coordinates, the result is direct distance in space.
J. Podani 2000. Introduction to the Exploration of Multivariate Biological Data. Backhuys Publishers,
Leiden, The Netherlands.
Jan Schulz. http://www.code10.info/.
Aim: skill to measure similarity of objects.
The answer needs to be updated
|ID||P||Question or exercise|
|3662||1|| Calculate Dice-Sørensen quotient of similarity between two forest stands where the coverage of tree species is as follows:
Stand 1: Alnus 32% Betula 5%, Picea 17%, Pinus 33%;
Stand 2: Pinus 32%, Picea 22%, Alnus 32%.
|3663||2|| Calculate Jaccardi similarity index from data in the previous exercise.
The result should fiffer from the Dice similarity.
Which of these indices is a better measurer for similarity? Give a reason.
|3664||1||The linked file contains long term mean precipitation data in Estonian meteorological stations. Is the monthly distribution of precipitation amount in Tartu more similar to the distribution in Tallinn or in Haanja?||Open|