course | course_year | question_number | tags | title | year | |||
---|---|---|---|---|---|---|---|---|
Statistics |
IB |
55 |
|
2.II.12H |
2002 |
For ten steel ingots from a production process the following measures of hardness were obtained:
On the assumption that the variation is well described by a normal density function obtain an estimate of the process mean.
The manufacturer claims that he is supplying steel with mean hardness 75 . Derive carefully a (generalized) likelihood ratio test of this claim. Knowing that for the data above
what is the result of the test at the
$\left.\begin{array}{lll}{[\text { Distribution }} & t_{9} & t_{10} \ 95 % \text { percentile } & 1.83 & 1.81 \ 97.5 % \text { percentile } & 2.26 & 2.23\end{array}\right]$