Statistics: 3 Problems

1. Big Mountain Power Company serves a region in which the following amounts of electricity are used annually (in millions of kilowatt hours).

Year Consumption
1999 352
2000 357
2001 362
2002 369
2003 380
2004 382
2005 389
2006 391
2007 394
2008 405

a) Plot the data.
b) Determine the regression equation and draw the line.
c) Forecast consumption for 2010 and 2011.

2. Based on the following table:

Occupation Family Income
Low Medium High Total
Homemaker 14 26 6 46
Blue Collar 16 42 16 74
White Collar 9 32 30 71
Professional 0 8 15 23
Total 39 108 67 214

Find the probability that a person selected would:
a. Have a low income
b. Be a professional
c. Have a high income
d. Be a white collar worker

3. Using the method of least square regression, construct an equation for the estimated regression line and draw it.

You are conducting research into the reasons for the high turnover among lab technicians in a large pharmaceutical company. You have theorized the amount of job satisfaction is related to turnover, that is satisfied people tend to stay. You use a standardized survey to measure job satisfaction and are interested in whether there are significant differences between individuals working in palliative drugs (improving the quality of life for terminal patients) and those working in therapeutic drugs (drugs that may cure terminal diseases).

You break the satisfaction scores into four categories: high satisfaction, moderate satisfaction, moderate dissatisfaction, and high dissatisfaction and create a cross-tabulation with the departments in which the technicians work.

High Sat. Mod. Sat Mod Dissat. High Dissat.
Palliative 8 12 30 22
Therapeutic 12 24 16 13

a. Is there a significant difference between these two areas?
b. What does it indicate about technicians satisfaction? Explain why you think this is.