论文题目：business statistic assignment

论文语种：英文

您的研究方向：business statistic

是否有数据处理要求：是

您的国家：澳大利亚

您的学校背景：澳洲monash univercity 大一

要求字数：主要是数字统计 字数没有太多要求 数字算的要正确 有描述的部分 也要描述清楚

论文用途：本科课程论文 BA Assignment

是否需要盲审（博士或硕士生有这个需要）：

补充要求和说明：我要要求高分大概在80%以上

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Assignment 2

Linear regression

This assignment is designed to test Unit Objective 4

Due date: 8th May 2009

This assignment is marked out of 50 and is worth 5% of the assessment in this unit. You must use Excel to generate the relevant output. The data for this assignment is in the file MCD2080_A2_T109.xls. The file has two worksheets, labelled Data, and Results.

The file is arranged so that all the required results can be presented in the worksheet labelled Results. The appropriate places for graphs, comments and tables are set out in this worksheet, and you are required to hand in a printed copy of the Results worksheet only. It is recommended that you first create the graphs and tables in the data worksheets, and then copy them to the appropriate places in the Results worksheet. In fact on some computers it is essential that you work in this way, as some networked computers have difficulty dealing with data analysis tools when data is selected from a different worksheet.

The assignment is to be handed in as a printout of the completed Results worksheet. Do not print out the data. The Results work sheet has been set up to make printing as easy as possible but it is your responsibility to ensure that all required information actually appears on the pages you hand in. Be sure to include your name and student ID in the appropriate cells near the top left corner of the Results worksheet.

While the presentation of the assignment is important, and some marks are designated for presentation, elaborate features are not required. Your work must be easy to read.

For questions involving written comments, the size of the textboxes on the Results worksheet are a general indication of the length of comments required (based on 11-point font.) It is however permissible to make some adjustment to the size and shape of the textboxes, especially when this is necessary to arrange the worksheet for printing.

Question

In this assignment, we investigate the relationship between the number of members of an emergency road service company and the number of phone calls it receives for help. In the Excel file MCD2080_A2_T109.xls, the work sheet Data consists of 49 months of data showing the number of members and the number of calls.

All tables, graphs and comments for this question should be placed in the appropriately labelled spaces in the worksheet Results.

(a)Which is the independent (or predictor) variable and which is the dependent (or response) variable in this problem? Give reasons for your choice and answer in Textbox (a)

4 marks

(b)Produce a scatter plot of the data (Graph (b)).The chart must have appropriate title and labels. Also you should rescale the graph axes to most clearly display the data. Based on the scatter plot, describe the type of relationship between the variables in Textbox (b).

9 marks

(c)Using the regression function in Excel, generate regression output for the data and place it where indicated in the Results worksheet.

i. Write down the line of best fit for the given data. Explain the meaning of any symbols used. (Textbox (c))

ii.State the value of the slope of the equation correct to three decimal places and give an interpretation of this value in Textbox (c).

iii.State the value of the intercept of the equation correct to three decimal places and give an interpretation of this value in Textbox (c). Is there a valid interpretation of the intercept? Explain briefly.

11 marks

(d)We now investigate whether the data provide sufficient evidence to indicate that there is a significant positive linear relationship between the number of members and the number of calls. Answer in Textbox (d).

i.State null and alternative hypotheses about the slope. (You are not required to type Greek letters with subscripts. You may use words or symbols instead of Greek letters. For example, H0 can be written as H_0, and β1 as beta_1, etc.)

ii.If the significance level were 5%, would the null hypothesis be rejected? If the significance level were 1%, would the null hypothesis be rejected? If the significance level were 0.5%, would the null hypothesis be rejected?

iii.Explain briefly what rejection of the null hypothesis would mean in this case.

9 marks

(e)Give the value of the coefficient of determination as a percentage to one decimal place. Hence describe the strength of the fit of this linear model to the data. Answer in Textbox (e)

4 marks

(f)Predict the number of calls when the number of members is:

i.400,000

ii.200,000

Comment on the reliability of each prediction. Answer in Textbox (f).

8 marks

Presentation:

5 marks (If your presentation is easy to read, you will get these 5 marks. Ease of reading is assisted by appropriate font size, borders, colour choice and labelling in graphs, and some care in spelling, grammar and punctuation. )