corrected some pages

Several small corrections were done to several proofs and definitions.

Author: JoramSoch

P/ind-self.md

@@ -36,7 +36,7 @@ username: "JoramSoch"
 **Theorem:** Let $E$ be a [random event](/D/reve). Then, $E$ is [independent of itself](/D/ind), if and only if its [probability](/D/prob) is zero or one:
 
 $$ \label{eq:ind-self}
-E \; \text{self-independent} \quad \Leftrightarrow \quad p(E) = 0 \quad \text{or} \quad p(E) = 1 \; .
+E \;\; \text{self-independent} \quad \Leftrightarrow \quad p(E) = 0 \quad \text{or} \quad p(E) = 1 \; .
 $$
 
 

P/wald-skew.md

@@ -114,7 +114,7 @@ $$ \label{eq:wald-skew-split2}
 g(t) = \frac{\alpha}{(\gamma^2-2t)^{3/2}}\exp\left[\alpha\gamma-\sqrt{\alpha^2(\gamma^2-2t)}\right] \; .
 $$
 
-With this decomposition, $M_X''\'(t) = f'(t) + g'(t)$. Applying the product rule to $f$ gives:
+With this decomposition, $M_X'\'\'(t) = f'(t) + g'(t)$. Applying the product rule to $f$ gives:
 
 $$ \label{eq:wald-skew-f}
 \begin{split}