ASSIGNMENT 1

MA 270 Statistical Analysis II

1. Briefly advise each of the following two (2) people on specific research studies that he or she might find useful. For each person, propose a reporting, descriptive, explanatory, and predictive study.

a. Manager of a full-service restaurant with high employee turnover (the management decision problem is known)

b. Director of Big Brothers/Big Sisters in charge of sponsor recruiting (the management decision problem has not yet been specified)

2. Distinguish between the items in the following sets and describe the significance of each in a research context:

a. Concept and construct

b. Deduction and induction

c. Concept and variable

d. Hypothesis and proposition

 

e. Theory and model

ASSIGNMENT 2

1. The quarterly production of pine lumber, in millions of board feet, by Northwest

Lumber since 1996 is shown in the following table:

 Quarter    

Year   Winter   Spring   Summer   Fall

1996   7.8   10.2   14.7   9.3  

1997   6.9   11.6   17.5   9.3

1998   8.9   9.7   15.3   10.1

1999   10.7   12.4   16.8   10.7

2000   9.2   13.6   17.1   10.3

a. Determine the typical seasonal pattern for the production data using the ratio-to-moving average method.

b. Interpret the pattern.

c. De-seasonalize the data and determine the linear trend equation.

d. Project the seasonally adjusted production for the four quarters of 2001.

2. Sales of roof material, by quarter, since 1994 for Carolina Home Construction, Inc. are shown below (in $000):

Quarter    

Year   I   II   III   IV  

1994   210   180   60   246  

1995   214   216   82   230

1996   246   228   91   280

1997   258   250   113   298

1998   279   267   116   304

1999   302   290   114   310

2000   321   291   120   320

a. Determine the typical seasonal patterns for sales using the ratio-to-moving average method.

b. Deseasonalize the data and determine the trend equation.

c. Project the sales for 2001, and then seasonally adjust each quarter.

3. The following is the number of retirees receiving benefits from the State Teachers Retirement System of Ohio from 1991 until 2000:

   
Year   Service       Year   Service       Year   Service  
                               
1991   58,436       1995   67,989       1999   78,341  
                               
1992   59,994       1996   70,448       2000   81,111  
                               
1993   61,515       1997   72,601              
                               
1994   63,182       1998   75,482              
                               

a. Determine the least squares trend equation. Use a linear equation.

b. Estimate the number of retirees that will be receiving benefits in 2003. Does this seem like a reasonable estimate based on the historical data?

c. By how much has the number of retirees increased or decreased (per year) on average during the period?