image

image

Friday, January 17, 2014

What's Your Function?

A)  http://www.economist.com/blogs/dailychart/2011/11/global-house-prices
This article in 'The Economist' discusses how the international housing market is picking up quickly, with great gains even in just the past year. It uses the markets of Britain, America, and Japan as its case studies, and compares the years from 1975 to 2013. In the case of this graph, the input is the year and the output is how good the housing market was for each country.

This function is linear because the pickup in the housing market for each country passes the VLT. The function is a mathematical model because the output is dependent on the input. As the years pass, the output (state of the nation's housing market) either becomes stronger or weaker. F(year)= house price index.

B)  http://www.accuweather.com/en/us/atlanta-ga/30303/weather-forecast/348181?partner=Googleonex
Jan. 17th: 11 mph
11 mph
10 mph
11 mph
Jan. 18th: 11 mph
10 mph
7 mph
8 mph
Above is Atlanta's wind forecast for the 17th and 18th. This relationship between date and speed of wind is not a function because there cannot be more than one wind speed during the whole day. This is saying that on these dates, the wind speeds were varying in the same city.

1 comment:

  1. mallisa,

    your examples are good and you did a nice job. however, for your first example, there are three separate functions and none of them are linear. for your second example, you need to specify which variables are outputs and which are inputs. if the date is the input and the wind speeds are the outputs, then yes, the relationship is not a function. however, if the situation is reversed then the relationship IS a function.

    professor little

    ReplyDelete