We have seen that the properties of the
sampling distribution of x bar help us estimate a range of
likely values for population mean m.
We can also rely on the properties of the
sample distribution to test hypotheses.
Example:
You are in charge of quality control in your food company. You sample
randomly four packs of cherry tomatoes, each labeled 1/2 lb. (227 g).
The average weight from your four boxes is 222 g. Obviously, we cannot expect boxes filled with whole tomatoes to all weigh exactly half a pound. Thus:
The average weight from your four boxes is 222 g. Obviously, we cannot expect boxes filled with whole tomatoes to all weigh exactly half a pound. Thus:
pIs the somewhat smaller weight simply due to chance
variation?
pIs it evidence that the calibrating machine that sorts
cherry tomatoes into packs needs revision?
cherry tomatoes into packs needs revision?
