# Statistics - "within" keywordWatch

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#1

X = # of hours past midday
F(X) = x, 0 <= x < 24

If you wanted to calculate if the random variable would be within 3 hours would it be P(X < 3) or P(X <= 3)?
0
6 years ago
#2
(Original post by JJMills)

X = # of hours past midday
F(X) = x, 0 <= x < 24

If you wanted to calculate if the random variable would be within 3 hours would it be P(X < 3) or P(X <= 3)?
P(X<=3), IMO.

Edit Changed my mind.

Consider what within 1 hour means. Would F(x) by 0 or 1?
0
#3
(Original post by ghostwalker)
P(X<=3), IMO.

Edit Changed my mind.

Consider what within 1 hour means. Would F(x) by 0 or 1?
Within, to me, implies under 1 hour (i.e. < not <=).

Just wanted to check if I was correct
0
6 years ago
#4
(Original post by JJMills)

X = # of hours past midday
F(X) = x, 0 <= x < 24

If you wanted to calculate if the random variable would be within 3 hours would it be P(X < 3) or P(X <= 3)?
Haha i see what is going on here.

Posted from TSR Mobile
0
6 years ago
#5
(Original post by JJMills)
Within, to me, implies under 1 hour (i.e. < not <=).

Just wanted to check if I was correct
< was my initial thought.

It looks to be a discrete uniform distribution.

Then I though about what the r.v. represented, or might represent, since there's no info there, and decided <=. But could be either I suspect.

Is there any background information?
0
6 years ago
#6
Im confused :/ generally within 1 hour means including 1 hour?
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#7
(Original post by ghostwalker)
< was my initial thought.

It looks to be a discrete uniform distribution.

Then I though about what the r.v. represented, or might represent, since there's no info there, and decided <=. But could be either I suspect.

Is there any background information?
If it said continuous uniform F(X < 3) would be the same as F(X <= 3), yes?

The keyword threw me as I was doing the problem and there isn't any background information other than what I posted.

(Original post by Putch1)
Im confused :/ generally within 1 hour means including 1 hour?
I'm really not sure.

Logically thinking I assumed it wasn't including 1 hour but I may be wrong.
0
6 years ago
#8
(Original post by JJMills)
If it said continuous uniform F(X < 3) would be the same as F(X <= 3), yes?
Yes.

What about F(X) = x, 0 <= x < 24 ?

If this is meant to be the cumulative distribution, then it should have a max value of 1, not 23.

I have interpreted this as a discrete distribution, but is it?
1
6 years ago
#9
(Original post by JJMills)
If it said continuous uniform F(X < 3) would be the same as F(X <= 3), yes?

The keyword threw me as I was doing the problem and there isn't any background information other than what I posted.

I'm really not sure.

Logically thinking I assumed it wasn't including 1 hour but I may be wrong.
I'm thinking that you can either take it as P(x<=1) or P(x<1) because it is a continuous distribution, since P(x=1) = 0
So both probabilities would be correct. I remember my teacher telling me this.
0
#10
(Original post by ghostwalker)
Yes.

What about F(X) = x, 0 <= x < 24 ?

If this is meant to be the cumulative distribution, then it should have a max value of 1, not 23.

I have interpreted this as a discrete distribution, but is it?
The question is made up and I obviously didn't put much attention into it.

I think I understand it now, thanks for your help though.
0
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