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0 votes
0 answers
27 views

How to get a CDF value from a PDF when the required CDF is not within the defined area?

I have a density function f(x, y) = 1/2 for 0 ≤ x ≤ y ≤ 2 and 0 elsewhere. I am being asked to find the CDF value F(1, 3), but as you can see the three is past the range of the defined triangle, what ...
Statsgyal's user avatar
1 vote
0 answers
44 views

Integral bounds for $x\geq yz$

I am having trouble understanding the integral bounds. From what side should my understanding go (first or second?): first: as $z$ is between zero and one, $y$ is also between zero and one, thus $x$ ...
VLC's user avatar
  • 2,527
0 votes
2 answers
419 views

Double integral setup - Uniform distribution

I am currently trying to understand a specific component of a probability problem involving setting up the proper bounds on a double integral. In the problem, $X_1$ and $X_2$ are independent Uniform $(...
John Coltrane's user avatar
-1 votes
1 answer
186 views

How do you find the bounds for a joint probability distribution function?

$$\begin{aligned} f(x, y) &=\begin{cases}1/(x^{2} y^{2}) & \text { für } &x \geq 1, y \geq 1 \\[1ex] 0 &&\text { sonst. }\end{cases}\\[2ex] V&:=X Y\end{aligned}$$ Find the ...
timtam's user avatar
  • 848
0 votes
1 answer
63 views

Estimate of the ratio $\frac{1}{\sqrt{2\pi}}e^{-x^2/2}(1-\text{erf}(x))$ (for standard normal distribution)

Define the probability density and cumulative probability of the standard Gaussian: $$ f(t) =\frac{1}{\sqrt{2\pi}} e^{-t^2/2}, \text{erf}(x) = \int_{-\infty}^x f(t) dt. $$ How can I prove that the ...
Ma Joad's user avatar
  • 7,534
1 vote
1 answer
386 views

What does this integral notation mean?

I'm talking about the integral part that is highlighted: Should I interpret the top one highlighted as the upper bound of integration and the bottom one as the lower bound? That's the only ...
Metrician's user avatar
  • 195
2 votes
2 answers
109 views

Is there a bound such that $\mathbb E(X^n)-\mathbb E(X)^n \le c; \quad n \in \mathbb Z_+.$

Any help on proving a bound such that: $\mathbb E(X^n)-\mathbb E(X)^n \le c; \quad n \in \mathbb Z_+.$ $X$ is the R.V. in the range of $[0,1]$ I am looking for something like Popoviciu's inequality ...
weidade3721's user avatar
3 votes
1 answer
167 views

Distances between $3$ random points on $[0,1]$

Suppose $3$ points are drawn uniformly at random from $[0,1]$. Call them $x_1,x_2,x_3$ with $x_1\leq x_2\leq x_3$. I am interested in the distances between them. Fix $0<a<b<1$. I want to ...
pwerth's user avatar
  • 3,880
1 vote
1 answer
2k views

Integrating the bivariate normal distribution [duplicate]

Let $X$ and $Y$ have the bivariate normal density function, $$ f(x, y) = \frac{1}{2 \pi \sqrt{1 - p^2}} \exp \left\{ - \frac{1}{2(1 - p^2)} (x^2 - 2pxy + y^2) \right\} $$ for fixed $p \in (-1, 1)$. ...
limitIntegral314's user avatar