SOLUTIONS MANUAL for Stochastic Modeling: Analysis and ...
SOLUTIONS MANUAL for Stochastic Modeling: Analysis and ...
SOLUTIONS MANUAL for Stochastic Modeling: Analysis and ...
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90 CHAPTER 7. CONTINUOUS-TIME PROCESSES<br />
19.<br />
an exponential distribution.<br />
This result shows that we can represent the holding time in a state (which is exponentially<br />
distributed) as the sum of a geometrically distributed number of exponentially<br />
distributed r<strong>and</strong>om variables with a common rate. This is precisely what uni<strong>for</strong>mization<br />
does.<br />
p ij (t) = e −g∗ t<br />
∞∑<br />
n=0<br />
q (n)<br />
ij<br />
= ˜p ij (t)+e −g∗ t<br />
≥<br />
˜p ij (t)<br />
because g ∗ > 0, t>0<strong>and</strong>q (n)<br />
ij ≥ 0.<br />
Notice that<br />
(g ∗ t) n<br />
n!<br />
∞∑<br />
n=n ∗ +1<br />
q (n)<br />
ij<br />
(g ∗ t) n<br />
n!<br />
e −g∗ t<br />
∞∑<br />
n=n ∗ +1<br />
q (n)<br />
ij<br />
(g ∗ t) n<br />
n!<br />
= 1− e −g∗ t<br />
≤<br />
1 − e −g∗ t<br />
n∗ ∑<br />
n=0<br />
n∗ ∑<br />
n=0<br />
q (n)<br />
ij<br />
(g ∗ t) n<br />
n!<br />
(g ∗ t) n<br />
n!<br />
because q (n)<br />
ij ≤ 1.<br />
20.<br />
Pr{Z 1 ≤ min<br />
j≠1<br />
Z j,H >t}<br />
= Pr{Z 1 ≤ Z 2 ,...,Z 1 ≤ Z k ,Z 1 >t,...,Z k >t}<br />
= Pr{t