Describing and summarizing relationships between variables.

 

 

 

Models help us describe and summarize relationships between variables. Understanding how process variables relate to each other helps businesses predict and improve performance. For example, a marketing manager might be interested in modeling the relationship between advertisement expenditures and sales revenues.

Consider the dataset below and respond to the questions that follow:

Advertisement ($’000) Sales ($’000)
1068 4489
1026 5611
767 3290
885 4113
1156 4883
1146 5425
892 4414
938 5506
769 3346
677 3673
1184 6542
1009 5088

• Construct a scatter plot with this data.
• Do you observe a relationship between both variables?
• Use Excel to fit a linear regression line to the data. What is the fitted regression model? (Hint: You can follow the steps outlined on page 497 of the textbook.)
• What is the slope? What does the slope tell us?Is the slope significant?
• What is the intercept? Is it meaningful?
• What is the value of the regression coefficient,r? What is the value of the coefficient of determination, r^2? What does r^2 tell us?
• Use the model to predict sales and the business spends $950,000 in advertisement. Does the model underestimate or overestimates ales?

 

 

Sample Solution

War contributed greatly to Roman expansion and the territory they accumulated as a result. It has been suggested that the Romans actively sought war as a way of conquering new territory and expanding their empire. However, it seems more likely that for the most part the Romans did not make war frivolously. War was seen as an honorable and sacred act, proven by the temples built to celebrate victory and the accumulation of new gods from places they conquered. All of these traditions support the idea that Romans held war in high regard and would typically need a purpose before going to war. Their commitment to the army was so ingrained and the fear of punishment so severe that soldiers would not abandon their group even when death was certain. Polybius writes, “Men in covering forces often choose certain death, refusing to leave their ranks even when vastly outnumbered, owing to dread of punishment they would later face.” (Polybius 376) Soldiers were also a valuable asset to Rome, the power and size of the army gave Rome legitimacy to deter foreign powers from invasion but also gain support from the people of Rome. Often when a new territory was conquered their taxation would be in the form of able men to act as soldiers in the Roman army. Using the time of a valuable general or losing soldiers lives without a worthy cause would have not made sense, and therefore pointless war is an unworthy expense. This idea is supported by the rigorous requirements that go into war preparation as well as the general disposition of the Romans. Polybius says about the Romans, “they do not want them to make attacks or initiate hostilities as much as to be ready and willing, when the battle is going against them and they are being hard pressed, to stand their ground and die on behalf of their country.” (Polybius 369) This gives one a good sense that Rome by no means was a victim but also cannot be considered an active aggressor or bully.

This question has been answered.

Get Answer
WeCreativez WhatsApp Support
Our customer support team is here to answer your questions. Ask us anything!
👋 Hi, Welcome to Compliant Papers.