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Coverage of tree species was estimated for six stands. Trees are in rows and stands (koht1 ...koht6) in columns in the attached file.
- Which two stands form the most similar pair of stands?
- Is their similarity the largest according to all quotients available in the SDC?
- Which pair of stands includes the most different stands?
- How to interpret different Euclidean distance between observations that have zero similarity?
Notice the following when calculating similarity coefficients using the similarity module
in the online calculator.
- Similarity between sites presented in rows is calculated according to numerical site characteristics in columns.
- The calculator does not allow empty cells (undefined values). Write 0 if a species is missing in a site.
- Input only raw data without column headers and totals. Uncheck Variable names are in the first row.
- Case numbers must be in the first column.
For this exercise, the empty cells must be filled with zeros and then the table must be transposed. In Excel: Copy → Paste special → Transpose.
- Check that the features of the first stand are in the first row in transposed table, features of the second stand in the second row etc.
- Check the presence of ID numbers in the first column.
- Copy the data to the input of the online calculator.
- Press Calculate.
- Notice that the first two rows of the results contain ID numbers of the pairs of cases.
- Notice also that the block distance and the Euclidean distance are distance metrics while the others are similarity metrics.