My book uses both of the functions $\epsilon _{X_i}(I_n)$ and $1_{X_i\in I_n}$ once with an equality sign, otherwise just the first one. Is this different notation for the same function?
Thanks in advance!
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Sign up to join this communityMy book uses both of the functions $\epsilon _{X_i}(I_n)$ and $1_{X_i\in I_n}$ once with an equality sign, otherwise just the first one. Is this different notation for the same function?
Thanks in advance!
Now I found the answer myselft, he use it to denote the discrete measure. http://en.wikipedia.org/wiki/Discrete_measure
$$\epsilon _{X_n}(A)=\{_{0, if X_n \setminus A}^{1, if X_n \in A}$$ .