00:01
Okay, given distribution, i mean given distribution x, which is a uniform distribution from 0 to theta, and theta is our parameter.
00:13
And to estimate this parameter theta, suppose we have n iid samples from x.
00:27
Okay, that means for each i, xi is a uniform distribution on 0 theta.
00:33
From this condition or equivalently for each xi, we know the density function for xi is equal to 1 over theta, when x is greater or equal to 0, that's equal to theta, is equal to 0 or else.
00:55
So by this property, we can write down the so -called joint likelihood function p.
01:02
P, we just use the vector x to represent x1, x2 to xn.
01:08
Okay, theta by the definition, which is just, this guy is just the multiplication of those density functions because they are independent.
01:19
So we have one over theta to the power n.
01:23
Okay, in principle, i can just write it in this way, but don't forget the most important term, the restriction, the indicative function, because this function is non -zero on this interval.
01:36
So this is the function for any i, x i is greater or equal to zero and less or equal to theta.
01:45
Okay, this is our joint likelihood function.
01:51
So to find the mle for theta, we are required to find some theta such that we find some theta hat such that p x bar, the vector x, theta hat, attains its maximum.
02:20
Okay, this is our requirement for theta hat.
02:24
Now let's consider our density function.
02:27
Function, to carefully consider this restriction here, we can write it as the first term is unchanged...