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# All these libraries were used in Week 3
library(devtools) 
library(Biobase)
## Loading required package: BiocGenerics
## Loading required package: parallel
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## Attaching package: 'BiocGenerics'
## The following objects are masked from 'package:parallel':
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##     clusterApply, clusterApplyLB, clusterCall, clusterEvalQ,
##     clusterExport, clusterMap, parApply, parCapply, parLapply,
##     parLapplyLB, parRapply, parSapply, parSapplyLB
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##     do.call, duplicated, eval, evalq, Filter, Find, get, grep,
##     grepl, intersect, is.unsorted, lapply, lengths, Map, mapply,
##     match, mget, order, paste, pmax, pmax.int, pmin, pmin.int,
##     Position, rank, rbind, Reduce, rownames, sapply, setdiff,
##     sort, table, tapply, union, unique, unsplit, which, which.max,
##     which.min
## Welcome to Bioconductor
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##     Vignettes contain introductory material; view with
##     'browseVignettes()'. To cite Bioconductor, see
##     'citation("Biobase")', and for packages 'citation("pkgname")'.
library(limma)
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## Attaching package: 'limma'
## The following object is masked from 'package:BiocGenerics':
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##     plotMA
library(edge)
library(genefilter)
library(snpStats)
## Loading required package: survival
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## Attaching package: 'survival'
## The following object is masked from 'package:edge':
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##     kidney
## Loading required package: Matrix
library(broom)

# library(MASS)
# library(DESeq2)
# library(qvalue) # Testing this in final two lectures of weeek 3

Q. Fit a linear model and a logistic regression model to the data for the 3rd SNP.

What are the coefficients for the SNP variable? How are they interpreted? (Hint: Don’t forget to recode the 0 values to NA for the SNP data)

data(for.exercise)
use <- seq(1, ncol(snps.10), 10)
sub.10 <- snps.10[,use]

Logistic regression model

snpdata = sub.10@.Data
status = subject.support$cc
snp1 = as.numeric(snpdata[,3])
snp1[snp1 == 0] = NA
glm1 = glm(status ~ snp1, family = "binomial")
tidy(glm1)
##          term   estimate std.error  statistic   p.value
## 1 (Intercept)  0.1772078 0.2199584  0.8056424 0.4204491
## 2        snp1 -0.1579378 0.1877400 -0.8412582 0.4002033

Q. Fit a linear model and a logistic regression model to the data for the 3rd SNP. What are the coefficients for the SNP variable? How are they interpreted? (Hint: Don’t forget to recode the 0 values to NA for the SNP data)


Linear Model = 0.54 Logistic Model = 0.18 Both models are fit on the additive scale. So in both cases the coefficient is the decrease in probability associated with each additional copy of the minor allele.


Linear Model = 0.54 Logistic Model = 0.18 Both models are fit on the additive scale. So in the linear model case, the coefficient is the decrease in probability associated with each additional copy of the minor allele. In the logistic regression case, it is the decrease in the log odds ratio associated with each additional copy of the minor allele.


Linear Model = -0.04 Logistic Model = -0.16 #### MCC1st-CORRECT Both models are fit on the additive scale. So in the linear model case, the coefficient is the decrease in probability associated with each additional copy of the minor allele. In the logistic regression case, it is the decrease in the log odds ratio associated with each additional copy of the minor allele.


Linear Model = -0.16 Logistic Model = -0.04 Both models are fit on the additive scale. So in the linear model case, the coefficient is the decrease in probability associated with each additional copy of the minor allele. In the logistic regression case, it is the decrease in the log odds ratio associated with each additional copy of the minor allele.

sessionInfo()
## R version 3.3.1 (2016-06-21)
## Platform: x86_64-pc-linux-gnu (64-bit)
## Running under: Ubuntu 16.04 LTS
## 
## locale:
##  [1] LC_CTYPE=en_US.UTF-8       LC_NUMERIC=C              
##  [3] LC_TIME=en_US.UTF-8        LC_COLLATE=en_US.UTF-8    
##  [5] LC_MONETARY=en_US.UTF-8    LC_MESSAGES=en_US.UTF-8   
##  [7] LC_PAPER=en_US.UTF-8       LC_NAME=C                 
##  [9] LC_ADDRESS=C               LC_TELEPHONE=C            
## [11] LC_MEASUREMENT=en_US.UTF-8 LC_IDENTIFICATION=C       
## 
## attached base packages:
## [1] parallel  stats     graphics  grDevices utils     datasets  methods  
## [8] base     
## 
## other attached packages:
##  [1] broom_0.4.2         snpStats_1.24.0     Matrix_1.2-8       
##  [4] survival_2.41-2     genefilter_1.56.0   edge_2.6.0         
##  [7] limma_3.30.13       Biobase_2.34.0      BiocGenerics_0.20.0
## [10] devtools_1.13.2    
## 
## loaded via a namespace (and not attached):
##  [1] qvalue_2.6.0         reshape2_1.4.2       splines_3.3.1       
##  [4] lattice_0.20-35      colorspace_1.3-2     htmltools_0.3.6     
##  [7] stats4_3.3.1         yaml_2.1.14          mgcv_1.8-17         
## [10] XML_3.98-1.7         rlang_0.1.1          nloptr_1.0.4        
## [13] foreign_0.8-68       withr_1.0.2          DBI_0.6-1           
## [16] snm_1.22.0           plyr_1.8.4           sva_3.22.0          
## [19] stringr_1.2.0        zlibbioc_1.20.0      munsell_0.4.3       
## [22] gtable_0.2.0         lfa_1.4.0            psych_1.7.5         
## [25] memoise_1.1.0        evaluate_0.10        knitr_1.16          
## [28] IRanges_2.8.1        AnnotationDbi_1.36.2 jackstraw_1.1       
## [31] Rcpp_0.12.11         xtable_1.8-2         corpcor_1.6.8       
## [34] scales_0.4.1         backports_1.1.0      S4Vectors_0.12.1    
## [37] annotate_1.52.1      lme4_1.1-12          mnormt_1.5-5        
## [40] ggplot2_2.2.1        digest_0.6.12        stringi_1.1.5       
## [43] dplyr_0.5.0          grid_3.3.1           rprojroot_1.2       
## [46] tools_3.3.1          bitops_1.0-6         magrittr_1.5        
## [49] lazyeval_0.2.0       RCurl_1.95-4.8       tibble_1.3.3        
## [52] RSQLite_1.1-2        tidyr_0.6.3          MASS_7.3-45         
## [55] assertthat_0.2.0     minqa_1.2.4          rmarkdown_1.6       
## [58] R6_2.2.1             nlme_3.1-131

EOF