Central location and Convexity: Difference between pages

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''Statistics''.
1. Broadly, convexity measures the curvature of the line representing the relationship between an instrument’s yield and its value. 
Duration and Modified duration can be used as the basis for straight line estimates of the rate of change of price/present value.  Convexity is an estimate of the rate of change of duration.  This is often visualised as the degree of 'curviness' of the line representing value versus yield.
Convexity is calculated as:


Measures of the central location (or position) of a frequency distribution give an indication of where the data is grouped. 
'''Sum [PV x t x (t+1)]/Sum(PV)'''
Three commonly used measures of central location are the mean, the median and the mode.


2. More strictly defined, convexity is the rate of change of duration, and modified convexity is the rate of change of modified duration, for small changes in yield from the given starting yield.
3. More loosely, the terms ''Convexity'' and ''Modified convexity'' are often used interchangeably.  Obviously this can lead to potential confusion, so it is important to clarify whether convexity or modified convexity is intended in any particular context.


== See also ==
== See also ==
* [[Average]]
* [[Duration]]
* [[Mean]]
* [[Modified convexity]]
* [[Median]]
* [[Modified duration]]
* [[Mode]]
* [[Position]]
 
* [[Skewness]]

Revision as of 14:19, 23 October 2012

1. Broadly, convexity measures the curvature of the line representing the relationship between an instrument’s yield and its value. Duration and Modified duration can be used as the basis for straight line estimates of the rate of change of price/present value. Convexity is an estimate of the rate of change of duration. This is often visualised as the degree of 'curviness' of the line representing value versus yield. Convexity is calculated as:

Sum [PV x t x (t+1)]/Sum(PV)

2. More strictly defined, convexity is the rate of change of duration, and modified convexity is the rate of change of modified duration, for small changes in yield from the given starting yield.

3. More loosely, the terms Convexity and Modified convexity are often used interchangeably. Obviously this can lead to potential confusion, so it is important to clarify whether convexity or modified convexity is intended in any particular context.

See also