Question: Trend in Iraq War casualties.While the United States was still actively fighting in the Iraq War, a news media outlet produced a graphic showing a dramatic decline in the annual number of American casualties. The number of deaths for the years 2003, 2004, 2005, and 2006 was (approximately) 475, 850, 820, and 130, respectively.

a.Create a time series plot showing the dramatic decline in the number of American deaths per year.

b.The graphic was based on data collected through February of 2006. Knowing this fact, why is the time series plot misleading?

c.What information would you like to have to construct a graph that accurately reflects the trend in American casualties from the Iraq War

Short Answer

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Answer

  1. The plot is an irregular trend.
  2. Misleading for showing the irregular trend.

For showing seasonal trends, it reflects in War

Step by step solution

01

Given information

From this information, the number of deaths of the years taken as , , and were(approximately) and respectively.

02

(a) Create a time series plot

We will utilize Excel to simplify things in this section.

Enter the following data into Excel:

Choose the Data. Select Scatterplot from the insert tab. The result is as follows

The plot is an irregular time series component.

03

(b) Define the cause of the misleading of plot

Here the plot is misleading because the graph shows irregular trends, so it will be misleading.

04

(c) Plotting the graph to find the correct information

For this issue, we plot the seasonal trend or trend. The graph is

The diagram is a seasonal type diagram. That means the number of deaths increases or decreases with the year seasonally.

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