[Forum SIS] Avviso di seminario :: Sun a DSS (Scienze Statistiche, Sapienza)

[Pierpaolo Brutti]

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 A v v i s o   d i   S e m i n a r i o
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Venerdì 13 Marzo, ore 11am
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Stanza 34
Dipartimento di Scienze Statistiche
Sapienza Università di Roma

SUN LEI

(Department of Statistical Sciences, University of Toronto)

terrà un seminario dal titolo

INCORPORATING PRIOR INFORMATION INTO MULTIPLE HYPOTHESIS
TESTING WITH APPLICATIONS TO LARGE-SCALE GENETIC STUDIES

tutti gli interessati sono invitati a partecipare.

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Maggiori informazioni sui seminari presso il DSS sono
consultabili a quest'indirizzo: http://goo.gl/Y6OQYm

Saluti

Pierpaolo Brutti

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ABSTRACT

A central issue in high-dimensional genetic studies is how to assess
statistical significance taking into account the inherent large-scale
multiple hypothesis testing.

To improve power, a number of studies have investigated the benefits
of utilizing available genomic and biological information, however,
the relative merits of different methods remain unclear. We focus on
the stratified FDR control (Sun et al., 2006, Genetic Epidemiology
30:519-530) and weighted p-value method (Genovese et al., 2006,
Biometrika 93:509-524). The two approaches model the prior info
distinctively. Weighted p-value approach converts the available prior
information to test-specific weighting factor and adjusts the p-values
accordingly. In contrast, stratified FDR divides tests into several
disjoint strata based on the prior information and applies the FDR
control separately in each stratum. We formulate the two approaches in
one framework and show the trade-off between power and robustness by
theoretical, simulation, and application studies. Robustness is
consequential in applications, safeguarding against potential
uninformative or even misleading prior information. To demonstrate the
practical relevance of these methods, I discuss two recent genome-wide
association studies of Cystic Fibrosis modifier genes, in which over
500,000 genetic markers are investigated for association with lung
functions in individuals with CF and the available prior is of
quantitative nature (Wright et al. 2011, Nature Genetics 43:539-548),
and for association with meconium ileus and the prior is of
categorical nature (Sun et al. 2012, Nature Genetics 44:562-569). If
time allows, I will briefly discuss additional interesting analytical
challenges in these studies.