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2.3.r. Phan ph6i chuAn N(uo') ...........;30

2.3.2.PhAnph6iStudent(n)............. ..,...................31

2.3.3. Phan ph6i Chi-binh phuong f'(n) ...:........32

i.l.q. PhAn ph6i Fisher F(m, n)..... .,.......................33

2.4. Phin ph6i xec su6t tren m5u nglu nhi6n :.............33

2.4.1. Miu ngdu nhi6n phdn ph6i chudn..................:................34

2.4.2. Miu ngiu nhi6n c6 cing ph6n ph6i .............37

2.4.3. PhAn ph6i cric th6ng ke thf tU ............. ........41

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3.1. Udc lugng ditim......... ........45

3.2.Utc lugng khodng ...............................51

Chuong 4. Thr;c hinh g thuy6t ki6m tlinh ..............59

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4.1.1. Kirim ttinh trung binh .......... .......59

4.1.2. Ki6m dinh phuong sai......... .......64

4.1.3. Ki6m dinh tf Ie.............. .............6s

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