Question

Answer the questions as indicated for scenarios 1-5. Note: You do not need to perform any of the procedures indicated.

Scenario 4:

A pharmaceutical manufacturer does a chemical analysis to check the potency of products. The standard release potency for cephalothin crystals is 910. An SRS of 16 lots gives the following potency data:

897 914 913 906 916 918 905 921

918 906 895 893 908 906 907 901

We wish to estimate the mean potency of products using a 95% confidence level.

A. Indicate whether the inference procedure needed is a confidence interval or a significance test.

B. Indicate whether the procedure involves one or two samples.

C. Name the inference method needed to answer the question posed.

D. Verify whether or not the conditions have been met for this inference procedure. Specifically, you need to list each condition and then explain how the condition was or was not met.

E. Determine if it is appropriate to perform the significance test or confidence interval (yes/no).

Answer 1

A:

Since we need to estimate the mean potency so 95% confidence interval for mean potency is needed.

B:

There is only sample namely "SRS of 16 lots".

That is procedure involves only one sample.

C:

Here standard deviation of population is unknown so t test ot t confidence will be used.

D:

It is given that sample is SRS so random condition has been fulfilled.

Each product is independent from other so independent condition has been fulfilled.

Following is the boxplot generated by excel:

Box Plot 890 895 900 905 910 915 920 925 х

Boxplot is almost symmetric. There is no outlier. So we can assume that data is normally distributed.

That is all conditions for t test or t confidence interval has been fulfilled.

E:

Yes it is appropriate because all conditions for t procedure has been fulfilled. We can use sample data to estimate the mean potency of products using a 95% confidence level.