Practice with
continuous
r.ve's
Law of
Total Probability
M
2
Discrete
D
Pr
E
fPrCE Y g fy g dy
ME
PrfEI
Pray
Law of Total
Expectation
Discrete
Continuous
F
x E XlY
k Pr Yek
w
F
X
fE X Y
y fyb dy
E PrCx xH D
Prcx
Y
D
xf
µ ylYdx
w
f
y
x y
Y F totalexpL Ky fy g dy Ef ace Poisson y f yeidy I law of total - - PDF document
r.ve's Practice with continuous Total Probability Law of Discrete 2 M D Pray PrfEI ME fPrCE Y g fy g dy Pr E Law of Total Expectation Discrete Continuous k Pr Yek E XlY F x w y fyb dy fE X Y F X E PrCx xH D Prcx Y D xf
Practice with
continuous
r.ve's
Law of
Total Probability
M
2
Discrete
D
E
ME
PrfEI
Pray
Law of Total
Discrete
Continuous
F
x E XlY
k Pr Yek
w
F
y fyb dy
Prcx
D
y
x y
wrandan
accidents
aperson has in ayear
is
Poisson
a
but 2
is
rn
A
exp l
instead
D
fraction
population that has
A
prfnoauidfa
kq.ie
is
a EEE
go
Prfrandompersonhas noaccidents
meg
Prfrandn
person
has
noact 2 9
Gd's
exppy Xnexpli
fxcxt.ae
X
Poussonly
e
e9dg
P4X k E
y
co
e4dg
s
EE XR
k
F
accidents forrandenpenseningeay
k
ace
Ky fyg dy
Poissony
I
law of total probe
Pr Xd
Pr XcY Y
fyGldy
Pr Xss
X nu
Y
g X
I
find
busing 4 2X
I
1
probdensityfn forY
2
4
X
f Cx Fx x
Recipe
for computingfyG
to
S 25
FyGy PrYes Find
CDF forY
Prf2XEg
Fyls
Pr Yes Pr g
as
nurse
Pr Xe
differentiateto get p.d.fr
dagFyG yFyG
2
w
intuition
i e to
see this
makes sense
Prfa
X sates
a
farepsilon
small
E fy
a
Pr
a ageYeates
E
E
fx E
Xv Nlp d
Y
aXtb Claim
Yn Nfaprtb
aha
Proof
Fyly
Pr Yey Pr
axtbey
dd
yfxfs.bz
aLfx Ia
e lEs nI
9
which is densityof
N aptb aka
Distributions
Joint CDF
F
y
x g
Pr X ex Yey
asb
f
dydx
jointdensity fu
x g
x y
f
x y
dxdy
I
Pr
a
X Laida
b
Ytbtdb
fC y dydx a flap dadb Marginal densityfor
so
x
x g dy
Conditional
prob mass fus
X
Y indep
fxycx.us 1 6 ly y
V xD
for
y with fyly
y yCx
fXYk
fy y conditional prob densityfn
f yay
fxkHyµ
X
Unif0,10
fXl
Too
10
ifX 3
F Y
E Y X x f lx dx
10
dx
2.5
O
discreteselting
XRY discretenu s
w
Uniffoyo Uniffo x
x Y y Pr
PrfY y X x Pray