... combination of factors: ease and documentation of the methodology, quality and user-friendliness of the software, the reputation of the RiskMetrics Group and familiarity with some of its other products, ... the bonds were held longer, reflecting a general recovery of downgraded bonds after the initial sell-off. A further argument is that, even if the bulk of the distribution appears normal, the ... sampling is based on the idea that one is really only concerned with the tail of the distribution, and will therefore sample more observations from the tail than from the rest of the distribution....