- Description

# HOLMES INSTITUTE FACULTY OF HIGHER EDUCATION HI6007 Group Assignment Due End of Week 10 WORTH 30% (Maximum 5 students in the group)

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**MS Excel must be used to perform any calculations/graphical presentations as required in this assignment **

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# Question 1 7 marks

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Below you are given the examination scores of 20 students (data set also provided in accompanying MS Excel file).

52 | 99 | 92 | 86 | 84 |

63 | 72 | 76 | 95 | 88 |

92 | 58 | 65 | 79 | 80 |

90 | 75 | 74 | 56 | 99 |

- Construct a frequency distribution, cumulative frequency distribution, relative frequency distribution, cumulative relative frequency distribution and percent frequency distribution for the data set using a class width of 10.
**(5 marks)**

- Construct a histogram showing the percent frequency distribution of the examination scores. Comment on the shape of the distribution.
**(2 marks)**

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# Question 2 8 marks

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Shown below is a portion of a computer output for a regression analysis relating supply (Y in thousands of units) and unit price (X in thousands of dollars).

# ANOVA

*df**SS*

Regression 1 354.689

Residual 39 7035.262

*Coefficients*** Standard Error** Intercept 54.0762.358

X 0.029 0.021

- What has been the sample size for this problem?
**(1 mark)**

- Determine whether or not demand and unit price are related. Use α = 0.05.
**(2 marks)**

Compute the coefficient of determination and fully interpret its meaning. Be very specific. c.

# (2 marks)

Compute the coefficient of correlation and explain the relationship between supply and

- unit price.
**(2 marks)**

- Predict the supply (in units) when the unit price is $50,000.
**(1 mark)****Question 3 6 marks**

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Allied Corporation wants to increase the productivity of its line workers. Four different programs have been suggested to help increase productivity. Twenty employees, making up a sample, have been randomly assigned to one of the four programs and their output for a day’s work has been recorded. You are given the results below (data set also provided in accompanying MS Excel file).

Program A | Program B | Program C | Program D |

150 | 150 | 185 | 175 |

130 | 120 | 220 | 150 |

120 | 135 | 190 | 120 |

180 | 160 | 180 | 130 |

145 | 110 | 175 | 175 |

- Construct an ANOVA table.
**(3 marks)**

- As the statistical consultant to Allied, what would you advise them? Use a .05 level of

significance. **(3 marks)**

# Question 4 9 marks

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A company has recorded data on the weekly sales for its product (*y*), the unit price of the competitor’s product (*x*1), and advertising expenditures (*x*2). The data resulting from a random sample of 7 weeks follows. Use Excel’s Regression Tool to answer the following questions (data set also provided in accompanying MS Excel file).

Week Price Advertising Sales

- .33 5 20
- .25 2 14
- .44 7 22
- .40 9 21
- .35 4 16
- .39 8 19
- .29 9 15

- What is the estimated regression equation? Show the regression output.
**(2 marks)**

- Determine whether the model is significant
. Use α = 0.10.*overall***(2 marks)**

- Determine if competitor’s price and advertising is
significantly related to*individually*

sales. Use α = 0.10. **(2 marks)**

Based on your answer to part (c), drop any insignificant independent variable(s) and d.

re-estimate the model. What is the new estimated regression equation? **(2 marks)**

- Interpret the slope coefficient(s) of the model from part (d).
**(1 marks)**

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