Posts Tagged ‘ factors ’

Multiple Factor Model – Building Fundamental Factors

February 4, 2012
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Multiple Factor Model – Building Fundamental Factors

This is the second post in the series about Multiple Factor Models. I will build on the code presented in the prior post, Multiple Factor Model – Fundamental Data, and I will show how to build Fundamental factors described in the CSFB Alpha Factor Framework. For details of the CSFB Alpha Factor Framework please...

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Multiple Factor Model – Fundamental Data

January 28, 2012
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Multiple Factor Model – Fundamental Data

The Multiple Factor Model can be used to decompose returns and calculate risk. Following are some examples of the Multiple Factor Models: The expected returns factor model: Commonality In The Determinants Of Expected Stock Returns by R. Haugen, N. Baker (1996) The expected returns factor model: CSFB Quantitative Research, Alpha Factor Framework on page...

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Generating stress scenarios: null correlation is not enough

December 28, 2010
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Generating stress scenarios: null correlation is not enough

In a recent post (here, by @teramonagi), Teramonagi mentioned the use of PCA to model yield curve, i.e. to obtain the three factor, "parallel shift", "twist" and "butterfly". As in Nelson & Siegel, if m is maturity, is the yield of the cu...

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Drop unused factor levels

February 4, 2008
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Drop unused factor levels

When creating a subset of a dataframe, I often exclude rows based on the level of a factor. However, the "levels" of the factor remain intact. This is the intended behavior of R, but it can cause problems in some cases. I finally discovered how to clea...

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Convert factors to numbers

November 29, 2007
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Convert factors to numbers

If you have a vector of factors it is easy to get the factor level; however, I always forget how to extract the factor value. I ran into the answer here.> x<-factor(c(round(rnorm(10),2),"A","B",NA))> x 1.61 1.12 1.26 0.09 -0.13 0.16 -...

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Reorder factor levels

October 3, 2007
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Reorder factor levels

Very often, especially when plotting data, I need to reorder the levels of a factor because the default order is alphabetical. There must be many ways of reordering the levels; however, I always forget which package to look in. A direct way of reorderi...

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