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[Studies in Computational Intelligence 481] Artur Babiarz, Robert Bieda, Karol Jędrasiak, Aleksander Nawrat (auth.), Aleksander Nawrat, Zygmunt Kuś (eds.) - Vision Based Systemsfor UAV Applications (2013, Sprin

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40 R. <strong>Bieda</strong> et al.<br />

Vector is the mean vector of the elements compos<strong>in</strong>g a given class. The<br />

value is the average to all classes of features variation.<br />

The scatter<strong>in</strong>g matrix of <strong>in</strong>ter-class<br />

<br />

,<br />

<br />

where is the global mean vector<br />

(32)<br />

<br />

<br />

<br />

(33)<br />

The greatness of def<strong>in</strong>es the average distance between given mean<br />

vectors of given classes.<br />

This is the form of the mixture of the matrix dispersal/scattered matrix:<br />

(34)<br />

Such matrix is known as the covariance matrix of the feature vectors <strong>in</strong> relation to<br />

the global mean vector of all the analyzed classes. It can be easily shown that this<br />

matrix can be determ<strong>in</strong>ed us<strong>in</strong>g the (29) and (32) values <strong>in</strong> their form:<br />

(35)<br />

The Fisher ratio describ<strong>in</strong>g the separation degree of the classes In the feature dimension<br />

is often def<strong>in</strong>ed <strong>in</strong> the follow<strong>in</strong>g way:<br />

(36)<br />

The construction of the transformation matrix is based on the problem of maximiz<strong>in</strong>g<br />

the ratio (36). The problem of maximiz<strong>in</strong>g is a classical problem of<br />

appo<strong>in</strong>t<strong>in</strong>g the <strong>in</strong>dividual value and the value of <strong>in</strong>dividual matrices correspond<strong>in</strong>g<br />

with them<br />

(37)<br />

where matrix is a diagonal matrix of which the elements on the diagonal are the<br />

<strong>in</strong>dividual values of matrix:<br />

D<br />

λ1<br />

0 0<br />

<br />

0 λ 0<br />

<br />

<br />

<br />

<br />

<br />

<br />

<br />

0 0 λl<br />

<br />

2<br />

= <br />

(38)

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