P(X=4) = .10 is correct
P(3≤ X<4)-P(-2≤ X<0) will give you P(-1 < X < 4) not P(-1 < X < 3)
I'm having trouble with grasping cdf's. If I have a cumulative distribution function
F(x) =
.0 ----- x<-2
.2 ----- -2 ≤ x< 0
.5 ----- 0 ≤ x < 1
.7 ----- 1 ≤ x < 3
.9 ----- 3 ≤ x < 4
1.0 ----- x ≥ 4
Im trying to evaluate P(-1 < X < 3) and P(X=4). For P(-1 < X < 3) im doing P(3≤ X<4)-P(-2≤ X<0) which gives me .7. For P(X=4) I subtract P(3<=X<4) from 1 giving me 1-.9=.10.
Im not sure I am doing this right though.
Last edited by bigbob; 10-06-2013 at 05:40 PM.
P(X=4) = .10 is correct
P(3≤ X<4)-P(-2≤ X<0) will give you P(-1 < X < 4) not P(-1 < X < 3)
Yes, positive 1 is included in P(1<=X<3)
Just so we're on e same page, this is a cumulative distribution function of a discrete probability distribution.
The graph of the cdf looks like this
From the graph you should be able to calculate the pdf
Yes, so
P(-2) = .2
P(-1) = 0
P(0) = .3
Note while the cdf is not continuous, it is defined for all points.
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