The most popular source of traffic for this blog is university students: I can't imagine people trying to write chess simulators in C

If you're an economics student, you're going to have to draw a lot of models. If you have a Mac, there's only one tool you need for graphing success: GraphSketcher. This is a free and open source tool that was originally designed by The Omni Group (the team behind OmniGraffle or "better not quite Visio for Mac").

*voluntarily*, but it's still one of my most popular blog posts each month. I didn't think posting any of my university assignment explanations from ten years ago would be popular; to use economic parlance, I thought the demand curve for my posts would be as flat as sales of Windows Phones. But the recurring cheques from Google AdSense seems to disagree with me, so I'm going to start posting my answers to economics assignments because none of the questions or answers have changed in last 129 years since Alfred Marshall's*Principles of Economics*.**Principles of Economics (1890).**

**Amazon did not exist in the year 1890 so students**

**had**

**to purchase over-priced textbooks in person.**

Download: GraphSketcher for Mac

Here are some tips for great success.

**Don't use the graphing function in Microsoft Excel.**You'll spend too much time trying to create the*"*correct*"*source data to generate the curves, and you've only got till morning to submit your assignment.**Don't use Photoshop.**You'll spend too much time messing around with layers, and trying to crack Photoshop.**Label your axis.**Specify the unit of measurement too, e.g.*Private spending ($ billions)***Use double lines to denote a jump in the axis.****Use big dots and letters to draw attention to "before and after".**Tell the story with your model. In the example below,*A*is the normal level of private spending/real GDP.*B*is what happens when we private spending is reduced, and*C*is what happens when it's increased.**Use arrows to tell stories about your model.**The lecturer/TA is a busy person: they are trying to trying to test you (and 250 other students) understanding of a model. They will spend 1 second looking at your graph to judge this.*If private spending goes up, what happens to real GDP?*You may know the answer,__but can you demonstrate to the lecturer/TA that you understand using only a graph with no associated written or verbal explanation__? In the example below, it's clear that when (C+I)_{0}shifts upward to (C+I)_{2}, this intersects GDP curve at a*higher*level. We indicate this with an 2 arrows: an upward arrow for the (C+I) curve shift, and a right arrow for the real GDP shift.**Put a zero on your graph.**No zero? One mark deducted!

I've uploaded some of my old graphs to get you started.

- Aggregate expenditure/output approach [download]
- Consumption Schedule graph [download]
- Investment demand curve with shifts graph [download]
- Investment demand curve graph [download]
- Net Exports schedule graph [download]
- Increases in price level graph [download]
- Inflationary gap graph [download]
- Built-in stability graph [download]

Aggregate expenditure/Output approach [download] |

Consumption Schedule graph [download] |

Investment demand curve with shifts graph [download] |

Investment demand curve graph [download] |

Net Exports schedule graph [download] |

Increases in price level graph [download] |

Inflationary gap graph [download] |

Built-in stability graph [download] |