A statistics student designed a study to see if there was an

A statistics student designed a study to see if there was any difference between brandname batteries and a generic brand.  To estimate the difference in mean lifetimes, he kept a batterypowered CD player continuously playing the same CD, with the volume control fixed at 5, and measured the time until no more music was heard through the headphones.  He measured the time in minutes until the sound stopped.  The data for 6 randomly selected batteries from a well known brand and 6 randomly selected batteries from a generic brand are in the excel file.  Based on other experiments, it is known that multiple measures of times for a brand of battery are approximately normally distributed.   

a) What are the experimental units in the study?  What is the response variable.  Quantitative or categorical?

b) Can we do inference based on a t distribution:  do these conditions apply?  

For each treatment group, does n 30 or is the response variable known to be normally distributed?   

random samples

c) Conduct a 4step significance test to determine if the batteries perform differently.

Solution