Coursework
First of all, I added another column to the table that showed the ‘Depreciation in value’ so I could refer to it in the project and make comparisons between it and other factors such as mileage, engine size, age etc. For the purposes of this project, ‘depreciation’ will refer to the current value as a percentage of the original price, rather than showing how much the price has fallen. I used the formula: D = C/O * 100. Where ‘D’ is depreciation, ‘C’ is current price, and ‘O’ is the original price. As I am investigating every car, I will not include a table as there is far too much data, therefore it will take up too much unnecessary space and paper.
The first factor that I will investigate to see if it affects the price of a second hand car is the age. I expected there to be a correlation so I decided to draw a scatter diagram. This is what I found.
This graph clearly shows that there is a negative correlation meaning that as the age increases, the price decreases.
The next factor that I will investigate to see if it affects the depreciation (see page 1) is the mileage. I decided to use another scatter diagram to see if there was any correlation between the two factors. This is what I found.
Again, this graph definitely shows that there is a negative correlation meaning that, generally, when the mileage increases, the price decreases. There are a few exceptions.
The next factor that I am going to investigate to see if it affects the depreciation (see page 1) is the nationality of the car. I am going to compare; French, British, Asian and American cars as there is a lot of information provided with these cars and there is more data to compare. With more data, it is easier to see correlation. First of all I am going to investigate to see how French cars hold their value. I will draw graphs for all the graphs and then make comparisons at the end. I will draw a line of best fit and compare the gradients for all the graphs; the one with the steepest gradient will hold its value the least well. I will find the gradient using the formula: y = mx+c. Where ‘y’ is the y axis, ‘x’ is the x axis, ‘m’ is the gradient and ‘c’ is the intercept.
In this scatter graph I am investigating how French cars hold their value. The gradient for this line is -5.6.
I will now investigate to see how British cars hold their values. The gradient for this line is -5.9.
I will now investigate to see how American cars hold their value. The gradient for this line is -4.5.
I will now investigate to see how Asian cars hold their value. The gradient for this line is -5.0.
From these graphs, it can be seen that that the one with data for British cars has the steepest gradient. This means that from this information, the British cars hold their value the best. It can also be seen that American cars hold their value the least well. From the data provided.
Conclusion:
From my investigation it can be seen that:
- There is a negative correlation between the age and the depreciation.
- There is a negative correlation between the mileage and the depreciation.
- That British cars hold their value the best.
- American cars are the worst at holding their value.