Table 4.
The diagnostic accuracy of LVQ networks for discrimination of two categories of vasospasm
| Number of neurons in Kohonen layer: 8 | Number of neurons in Kohonen layer: 16 | ||||
|---|---|---|---|---|---|
| (a) Vasospasm is categorized as class 1—normal (VA1), and class 2—mild, moderate, or severe [VA(2–3–4)] | |||||
| VA1-des | VA(2–3–4)-des | VA1-des | VA(2–3–4)-des | ||
| VA1-act | 0.9469 | 0.3556 | VA1-act | 0.9292 | 0.1778 |
| VA(2–3–4)-act | 0.0531 | 0.6444 | VA(2–3–4)-act | 0.0708 | 0.8222 |
| Overall classification rate=0.7957 | Overall classification rate=0.8757 | ||||
| (b) Vasospasm is categorized as class 1—normal or mild [VA(1–2)], and class 2—moderate or severe [VA(3–4)] | |||||
| VA(1–2)-des | VA(3–4)-des | VA(1–2)-des | VA(3–4)-des | ||
| VA(1–2)-act | 0.9077 | 0.2143 | VA(1–2)-act | 0.9846 | 0.1429 |
| VA(3–4)-act | 0.0923 | 0.7857 | VA(3–4)-act | 0.0154 | 0.8571 |
| Overall classification rate=0.8467 | Overall classification rate=0.9209 | ||||
| (c) Vasospasm is categorized as class 1—normal, mild, or moderate [VA(1–2–3)], and class 2—severe (V4) | |||||
| VA(1–2–3)-des | VA4-des | VA(1–2–3)-des | VA4-des | ||
| VA(1–2–3)-act | 0.9866 | 0.6667 | VA(1–2–3)-act | 0.9866 | 0.2222 |
| VA4-act | 0.0134 | 0.3333 | VA4-act | 0.0134 | 0.7778 |
| Overall classification rate=0.6600 | Overall classification rate=0.8822 | ||||
Confusion matrices detail code of actual (act) class (rows) versus code of desired (des) class (columns). All LVQ networks contained three input variables (TCCS velocity data) and two output variables (categories of vasospasm)