Convergence in distribution

AI Thread Summary
The discussion focuses on proving the continuous mapping theorem, which states that if X_n converges in distribution to X, then h(X_n) converges in distribution to h(X) for any continuous function h. The participants express an understanding of the theorem's intuitive appeal but struggle with the mathematical proof, specifically avoiding the Skorokhod representation theorem. They reference the definitions of convergence in distribution and the properties of bounded continuous functions to support their arguments. The conversation highlights the importance of demonstrating that the composition of continuous functions preserves the convergence properties. Overall, the participants seek clarity on the proof while acknowledging the foundational concepts involved.
shan
Messages
56
Reaction score
0
Given the definition:
For real-valued random variables X_n, n\geq1 and X, then X_n\stackrel{D}{\rightarrow}X if for every bounded continuous function g: R \rightarrow R, E_n[g(X_n)]\rightarrow E[g(X)]

I want to prove the continuous mapping theorem:
If X_n\stackrel{D}{\rightarrow}X then h(X_n)\stackrel{D}{\rightarrow}h(X) for any continuous function h: R \rightarrow R
without using Skorokhod's representation theorem.

The theorem makes sense to me intuitively but I'm lost as to how to prove it mathematically.

Edit: apologies for the really bad latex, my browser keeps hanging on the preview/save
 
Last edited:
Mathematics news on Phys.org
If anyone was interested:

Say h(Y_n) = Z_n, h(Y) = Z

E(g(Z_n)) \rightarrow E(g(Z)) for every g that is bounded and continuous (from definition)

E(f(Y_n)) \rightarrow E(f(Y)) for every f that is bounded and continuous (from definition)

E(g(h(Y_n)) \rightarrow E(g(h(Y)) is true because h is continuous and g o h is also continuous, h is also bounded by g
 
Fermat's Last Theorem has long been one of the most famous mathematical problems, and is now one of the most famous theorems. It simply states that the equation $$ a^n+b^n=c^n $$ has no solutions with positive integers if ##n>2.## It was named after Pierre de Fermat (1607-1665). The problem itself stems from the book Arithmetica by Diophantus of Alexandria. It gained popularity because Fermat noted in his copy "Cubum autem in duos cubos, aut quadratoquadratum in duos quadratoquadratos, et...
Insights auto threads is broken atm, so I'm manually creating these for new Insight articles. In Dirac’s Principles of Quantum Mechanics published in 1930 he introduced a “convenient notation” he referred to as a “delta function” which he treated as a continuum analog to the discrete Kronecker delta. The Kronecker delta is simply the indexed components of the identity operator in matrix algebra Source: https://www.physicsforums.com/insights/what-exactly-is-diracs-delta-function/ by...
Thread 'Imaginary Pythagorus'
I posted this in the Lame Math thread, but it's got me thinking. Is there any validity to this? Or is it really just a mathematical trick? Naively, I see that i2 + plus 12 does equal zero2. But does this have a meaning? I know one can treat the imaginary number line as just another axis like the reals, but does that mean this does represent a triangle in the complex plane with a hypotenuse of length zero? Ibix offered a rendering of the diagram using what I assume is matrix* notation...

Similar threads

Replies
17
Views
1K
Replies
3
Views
1K
Replies
13
Views
2K
Replies
125
Views
19K
Replies
2
Views
2K
Replies
1
Views
1K
Back
Top