background image

Egzamin dla Aktuariuszy z 5 czerwca 2006 r. 
 
Prawdopodobieństwo i Statystyka 
 
Zadanie 1 
 

(

) (

)

(

)

(

)

Z

Y

X

E

Z

E

Z

Z

Y

X

EE

Z

Y

X

E

2

2

2

2

2

2

)

(

)

(

)

(

=

=

 

E(X-Y)=0 
Var(X-Y)=varX+varY-2cov(X,Y)=4+1-2=3 
Cov(X-Y,Z)=cov(X,Z)-cov(Y,Z)=2-1=1 

(

)

Z

Z

Y

X

E

4

1

=

  z regresji 

(

)

4

11

3

12

11

3

4

3

1

1

var

=

=

=

Z

Y

X

 

(

)

14

3

11

4

3

16

1

4

4

11

16

1

4

11

16

1

4

11

)

(

2

4

2

2

2

2

2

=

+

=

+

=

+

=





+

=

EZ

EZ

Z

Z

E

Z

Y

X

E

 

(

)

1

0

1

0

2

)

,

cov(

)

,

cov(

)

(

=

+

=

+

=

=

EYEZ

Z

Y

EXEZ

Z

X

EYZ

EXZ

Z

Y

X

E

 

var((X-Y)Z)=14-1=13 
 
Zadanie 2 
 

(

)

(

)

(

)

4

4

6

6

 

i

 

4

10

10

7

7

10

=

=

=

=

=

S

P

S

S

P

S

S

P

ODP

 

(

)

(

)

(

)

(

)

(

)

4

5

,

0

1

4

4

7

1

4

6

1

4

6

10

10

10

10

7

10

7

10

7

=

=

=

=

=

=

=

>

=

=

S

P

S

P

S

S

P

S

S

P

S

S

P

 

(

)

(

)

(

)

10

10

10

10

10

5

,

0

4

4

5

,

0

1

4

=

=

=

=

=

S

P

S

P

S

P

ODP

 

(

)

4

10

=

S

P

 - moŜliwe tylko gdy 7x jedynka 3razy –1 

Z tego: 

(

)

10

10

10

10

2

120

2

6

10

9

8

2

7

10

4

=

=





=

=

S

P

 

1024

119

2

1

120

10

=

=

ODP

 

 
Zadanie 3 
 

(

)

1

5

ˆ

1

1

+

+

Π

=

θ

i

θ

x

θ

L

 

(

)

+

+

=

i

θ

x

θ

θ

L

1

ln

)

1

(

ln

5

ln

1

ˆ

 

(

)

(

)

+

=

=

+

=

i

i

x

θ

x

θ

θ

1

ln

5

ˆ

0

1

ln

5

1

1

 

background image

 

 

analogicznie: 

(

)

+

=

i

y

θ

1

ln

4

ˆ

2

 

(

)

(

)

+

=

+

=

<

=

<

+

1

0

1

)

(

1

)

1

(

1

)

1

ln(

t

e

t

θ

θ

t

θ

wykl

e

x

θ

e

X

P

t

X

P

 

Γ

+

)

1

ln(

X

 

dla X mającego rozkład gamma: 

(

)

Γ

Γ

=

Γ

=

<

θ

t

t

w

x

θ

e

θ

w

θ

e

x

θ

t

X

θ

P

0

0

5

4

5

4

5

)

1

,

5

(

)

5

(

)

5

(

 

(

)

Γ

+

)

1

,

4

(

1

ln

i

y

θ

 

dla X mającego rozkład gamma(n,1) 

)

2

(

)

2

(

2

n

χ

t

X

P

<

 

teraz dla 

)

10

(

),

8

(

2

2

χ

X

χ

Y

 

}

299

,

0

35

,

3

1

)

95

,

0

(

1

10

8

5

4

ˆ

ˆ

)

8

,

10

(

)

10

,

8

(

2

1

=

=

<

=

<

=



<

F

F

kw

a

X

Y

P

a

X

Y

P

a

θ

θ

P

 

(

)

072

,

3

)

95

,

0

(

05

,

0

)

10

,

8

(

ˆ

ˆ

)

10

,

8

(

2

1

=

=

>

=



>

F

kw

a

F

P

b

θ

θ

P

 

 
Zadanie 4 
 

 

( ) ( ) ( ) ( ) ( ) ( ) (

)

b

III

P

III

A

P

b

II

P

II

A

P

b

I

P

I

A

P

b

A

P

2

2

2

2

+

+

=

 

( ) ( )

( ) ( )

(

) (

)

)

2

(

)

(

2

2

,

)

2

(

)

(

2

2

,

)

2

(

)

(

2

2

b

P

III

P

III

b

P

b

III

P

b

P

II

P

II

b

P

b

II

P

b

P

I

P

I

b

P

b

I

P

=

=

=

 

3

1

3

1

10

1

10

3

10

6

3

1

2

5

2

2

2

5

2

3

2

5

2

4

)

2

(

=





+

+

=









+









+









=

b

P

 

( )

( )

(

)

10

1

2

,

10

3

3

1

3

1

10

3

2

,

5

3

3

1

3

1

5

3

2

=

=

=

=

=

b

III

P

b

II

P

b

I

P

 

30

15

2

1

50

1

6

18

10

1

5

1

10

3

5

2

5

3

5

3

=

=

+

+

=

+

+

=

ODP

 

 

background image

Zadanie 5 
 

2

2

2

2

2

Z

V

Y

V

Z

V

Y

ZV

X

=

=

=

 

)

1

,

0

(

V

 

=

<

+

=

:

)

1

,

1

(

1

2

2

2

2

Z

Y

X

X

Z

 

 

2

2

1

1

Z

V

y

Z

VZ

Z

y

Z

V

x

V

z

X

=

=

=

=

 

(

)

0

1

1

1

1

1

1

1

2

2

2

2

2

2

2

2

2

=

+

=

+

=

=

Z

V

Z

V

Z

Z

V

Z

V

Z

Z

V

Z

Z

VZ

Z

V

D

 

)

1

,

0

(

),

1

,

1

(

   

1

2

)

,

(

2

Π

=

V

Z

Z

V

V

Z

f

 

Π

=

=

Γ

Π

Π

=

Π

=

1

1

2

)

1

,

0

(

   

2

2

)

5

,

0

(

2

2

1

2

)

(

v

v

v

dz

z

v

v

f

8

7

6

 

 
Zadanie 6 
 

i

 - czas oczekiwania na i-ty numer 

1

1

=

X

  

( ) ( ) ( ) ( ) ( )

6

5

4

3

2

1

X

E

X

E

X

E

X

E

X

E

ODP

+

+

+

+

+

=

 

i

 czas oczekiwania na sukces z 

6

7

i

p

=

 

(

)

=

=

6

7

6

1

1

i

i

k

X

P

k

i

 - przesunięty geometryczny 

Z tego: 

i

i

i

i

i

i

i

i

EX

i

=

+

=

+

=

+

=

7

6

7

7

1

1

7

1

1

7

6

6

1

 

7

,

14

20

14

2

12

4

6

5

6

12

6

2

6

3

6

4

6

5

6

1

=

+

+

=

+

+

=

+

+

+

+

+

=

ODP

 

 
Zadanie 7 
 

(

)

(

)

...

0

2

1

4

4

3

3

2

2

1

1

1

=

+

+

+

=

X

m

X

a

X

a

X

a

X

a

E

a

 

 
 
 
 
 

background image

(

)

(

)

(

)

(

)

(

)

(

)

(

)

(

)

(

)

(

)

(

)

(

)

=

+

+

+

=

+

+

+

=

+

+

+

=

+

+

+

4

4

3

3

4

2

2

4

1

1

2

4

4

3

3

4

4

3

2

2

3

1

1

2

3

3

2

2

4

4

3

2

3

2

1

1

2

2

2

1

4

1

4

3

1

3

2

1

2

2

1

1

mEX

X

X

E

a

X

X

E

a

X

X

E

a

EX

a

mEX

X

X

E

a

X

X

E

a

X

X

E

a

EX

a

mEX

X

X

E

a

X

X

E

a

X

X

E

a

EX

a

mEX

X

X

E

a

X

X

E

a

X

X

E

a

EX

a

 

2

2

4

2

2

3

2

2

2

2

2

1

32

18

8

2

m

EX

m

EX

m

EX

m

EX

=

=

=

=

 

im

EX

m

EX

i

=

=

1

20

1

,

15

1

,

10

1

,

5

1

4

3

2

1

=

=

=

=

a

a

a

a

 

+

+

+

+

+

+

+

4

2

4

2

3

2

3

2

4

1

4

1

3

1

3

1

2

2

2

2

2

1

2

1

2

1

2

1

2

2

2

2

2

[

X

X

a

a

X

X

a

a

X

X

a

a

X

X

a

a

X

a

X

X

a

a

X

a

E

 

(

)

2

2

4

4

3

3

2

2

1

1

2

4

2

4

4

3

4

3

2

3

2

3

5

1

]

2

2

m

m

X

a

X

a

X

a

X

a

m

X

a

X

X

a

a

X

a

=

+

+

+

+

+

+

+

 

 
Zadanie 8 
 

(

)

i

θ

θ

i

θ

i

θ

i

X

STAT

X

θ

θ

X

θ

X

θ

L

Π

=

Π





=

Π

Π

=

1

2

1

2

6

1

2

1

6

1

1

6

2

 

(

)

(

)

<

=

>

=

>

Π

t

X

P

t

X

P

t

X

P

i

i

i

1

ln

ln

ln

ln

 

(

)

(

)

=

=

>

=

<

=

<

1

1

)

(

1

1

ln

t

e

θ

t

θ

t

t

i

θ

wykl

e

x

θ

e

X

P

e

X

P

t

X

P

 

Γ

=

Γ

)

1

,

6

(

  

1

  

dla

  

)

,

6

(

ln

θ

θ

X

i

 

=

=

=

=

=

Γ

=

<

t

t

x

i

t

χ

x

t

t

x

e

x

t

X

P

1

ln

2

0

2

1

ln

0

5

0

226

,

5

1

ln

2

)

12

(

2

2

)

6

(

1

1

ln

ln

 

moc: 

=

=

=

Γ

=

<

2

226

,

5

0

226

,

5

3

0

2

3

5

6

1

79

,

0

)

12

(

2

3

)

6

(

3

2

226

,

5

ln

χ

t

x

e

x

X

P

x

i

 

lub liczymy: 

=

...

3

5

x

e

x

   i  wychodzi 

 
Zadanie 9 
 

(

) (

) (

) (

)

(

)

g

g

Y

P

Y

P

X

P

X

P

Y

P

n

n

n

n

n

4

1

2

1

1

4

1

2

1

1

2

1

1

1

1

+

=

+

=

=

+

=

 

3

2

3

4

2

1

2

1

4

3

=

=

=

g

g

 

 
 
 
 
 

background image

Zadanie 10 
 

(

)

(

)

(

)(

)

(

)

>

+

+

=

>

t

x

x

x

y

P

t

e

e

P

i

i

i

i

x

y

x

y

i

i

i

i

ln

2

1

1

2

0

2

2

2

1

0

2

2

 

( )

1

,

i

i

x

N

Y

 

(

)(

)

(

)

(

)

2

0

1

;

0

1

:

+

+

i

i

i

i

x

N

x

x

y

H

 

(

)(

)

(

)

(

)

(

)

=

+

+

+

+

X

x

x

N

x

x

x

y

i

i

i

i

i

i

2

2

2

1

;

2

1

2

1

1

 

(

)

(

)

(

)

(

)

=





+

+

+

>

+

+

+

05

,

0

1

2

1

ln

1

2

1

2

2

2

2

0

i

i

i

i

x

x

t

x

x

X

P

 odpowiedź (A) bo 1,645