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Jan 17, 2023 at 19:36 comment added James C @Dave I see. Thanks!
Jan 17, 2023 at 19:28 comment added Dave @JamesC That sounds like a good topic for a new question to post separately. // You're getting closer when you have the $\sqrt n$ only on the left, but it is not quite right. The fully correct version would give some kind of arrow to denote convergence, perhaps even with a $d$ up top to denote convergence in distribution: $\sqrt n \bar X_n \overset{d}{\rightarrow} N(\mathbb E\left[X\right], \sigma)$. The standard way to write the theorem would have the convergence be to $N(0,1)$, but that's just a matter of some algebra.
Jan 17, 2023 at 19:24 comment added James C @Dave Another question. Hope you don't mind. In practice, is there a $n$-value that we use to apply CLT? We know that $\sqrt n \bar X_n$ converges to a normal distribution, but we do not know how fast the convergence is.
Jan 17, 2023 at 19:20 comment added James C @Dave so if I fix my statement as $\sqrt{n} \bar X_n \sim \mathcal N(\mathbb E[X], \sigma)$, then the statement becomes correct. Is this what you mean?
Jan 17, 2023 at 19:11 comment added Dave @JamesC Did you read what Aksakal wrote in the link by Jbowman? "Since your right hand side is changing, it's difficult to prove statements about this convergence relation, and I mean impossible by difficult." If so, what remains unclear?
Jan 17, 2023 at 19:09 comment added James C @jbowman Would you elaborate why my definition of CLT is incorrect? en.wikipedia.org/wiki/Central_limit_theorem#Classical_CLT
Jan 16, 2023 at 23:48 comment added Glen_b @James Your notation is off (among other things, you conflate standard deviations with estimates). With CIs write a pivotal quantity (or in this case an asymptotically pivotal quantity) and use not just CLT but also Slutsky's theorem to get a suitable distribution for the pivotal quantity, and hence the CI for the parameter. Different CIs dont need to have the same length, you just need 1-alpha of them to overlap the parameter.
Jan 16, 2023 at 22:15 comment added jbowman 1. The confidence intervals having the same length a) will never occur if the random variates are from a continuous distribution and b) is irrelevant. 2. Your definition of the central limit theorem is incorrect: see stats.stackexchange.com/questions/174734/… for some clarification.
Jan 16, 2023 at 21:57 history asked James C CC BY-SA 4.0