| written 6.6 years ago by | • modified 5.8 years ago |
| Object | Attribute 1 (X) | Attribute 2 (Y) |
|---|---|---|
| A | 2 | 2 |
| B | 3 | 2 |
| C | 1 | 1 |
| D | 3 | 1 |
| E | 1.5 | 1.5 |
| written 6.6 years ago by | • modified 5.8 years ago |
| Object | Attribute 1 (X) | Attribute 2 (Y) |
|---|---|---|
| A | 2 | 2 |
| B | 3 | 2 |
| C | 1 | 1 |
| D | 3 | 1 |
| E | 1.5 | 1.5 |
| written 6.6 years ago by | • modified 6.6 years ago |
Solution:
| Object | Attribute 1 (X) | Attribute 2 (Y) |
|---|---|---|
| A | 2 | 2 |
| B | 3 | 2 |
| C | 1 | 1 |
| D | 3 | 1 |
| E | 1.5 | 1.5 |
For simplicity we can find the adjacency matrix which gives distances of all object from each other. Using Euclidean distance we have
$\begin{aligned} \mathrm{D}(\mathrm{i}, \mathrm{j}) &=\sqrt{\left|\mathrm{x}_{2}-\mathrm{x}_{1}\right|^{2}+\left|\mathrm{y}_{2}-\mathrm{y}_{1}\right|^{2}} \\ \mathrm{D}(\mathrm{A}, \mathrm{B}) &=\sqrt{(2-3)^{2}+(2-2)^{2}}=1 \end{aligned}$
Similarly we can compute for the rest.
| A | B | C | D | E | |
|---|---|---|---|---|---|
| A | 0 | ||||
| B | 1 | 0 | |||
| C | 1.41 | 2.24 | 0 | ||
| D | 1.41 | 1 | 2 | 0 | |
| E | 1.58 | 2.12 | 0.71 | 1.58 | 0 |
(i) Singlelink:
step 1: Since $C, E$ is minimum we can combine clusters $C, E$
| - | A | B | (C,E) | D |
|---|---|---|---|---|
| A | 0 | |||
| B | 1 | 0 | ||
| C | 1.41 | 2.12 | 0 | |
| D | 1.41 | 1 | 1.58 | 0 |
Step 2: Now $\mathrm{A}$ and $\mathrm{B}$ is having minimum value therefore we merge these two clusters.
| - | (A,B) | (C,E) | D |
|---|---|---|---|
| (A,B) | 0 | ||
| (C,E) | 1.41 | 0 | |
| D | 1 | 1.58 | 0 |
Step 3 : Cluster $(\mathrm{A}, \mathrm{B})$ and $\mathrm{D}$ can be merged together as they are having minimum distance value
| - | (A,B,D) | (C,E) |
|---|---|---|
| (A,B,D) | 0 | |
| (C,E) | 1.41 | 0 |
Step 4 : In the last step there are only two clusters to be combined they are, $(\mathrm{A}, \mathrm{B}, \mathrm{D})$ and $(\mathrm{C}, \mathrm{E})$
Now the final dendrogram is
