August 2003

Vol. 5, No. 8


Quality Quiz
from Professor Cleary

Congratulations! 
You're right!

Ben N. Jayle actually hit the right answer. His motive may have been to do anything to support the need for air conditioning, but in any case, he was right about the t value.

In the chart, it is clear that the regression line is y =13.44 + 1.66x, with a t value of 8.97. The standard procedure is to set up a hypothesis that there is no relationship between x and y. If that hypothesis is rejected, this means that x and y are indeed related. The t statistic is used to determine whether there is a significant relationship between x and y. The ratio is:
where 

    B1-b1
t= -------
     Sb1

B1= hypothesis value for b1, typically = 0

b1= calculated value for the regression coefficient

Sb1= the error associated with determining the value for b

Thus, a large value for t suggests that there is little error in calculating b, so one can safely assume that x and y are related.

While air conditioning may not represent the next step in Ben N. Jayle's area, at least the statistical analysis suggests that high temperatures are not good for locks. Ben loves to be right.


 

Copyright 2003 PQ Systems.

Please direct questions or problems regarding this web site to the Webmaster.