Prediction Line

The following data (stored in the file ) represent the   nationwide highest yield of different types of accounts (extracted from   Bankrate.com, March 31, 2008):       Money Market Six Month CD   4 3.85   3.82 3.6   3.8 3.6   3.75 3.45   3.75 3.43       

a. At the   0.05 level of significance, is there evidence of a difference in the mean   yields of the different accounts?      

 b. If   appropriate, determine which accounts differ in mean yields       

c. At the   0.05 level of significance, is there evidence of a difference in the   variation in yields among the different accounts?       

d. What   effect does your result in (c) have on the validity of the results in (a) and   (b)?    

  Question

Where people turn to for news is different for various age   groups. A study indicated where different age groups primarily get their   news:       

MEDIA Under   36 36-50 50+   Local TV 107   119 133   National TV   73 102 127 Radio 75 97   109   Local   Newspaper 52 79 107   Internet 95   83 76    

At the 0.05   level of significance, is there evidence of a significant relationship   between the age group and where people primarily get their news? If so,   explain the relationship.    

   Question

Fitting a   straight line to a set of data yields the following prediction line:   Yi = 2 + 5Xi   

a. Interpret the meaning of the Y   intercept, b0.  

 b. Interpret the meaning of the slope,   b1.   

c. Predict the value of Y for X = 3.