add new links to index.md

Author: luozda

index.md

@@ -8,15 +8,15 @@ This is site is meant to serve as a directory for the amazing content the
 community has created around the Data Science Specialization. If you are
 interested in contributing [click here](https://github.com/DataScienceSpecialization/DataScienceSpecialization.github.io#contributing).
 
-1. [The Data Scientist’s Toolbox](/toolbox/)
-2. [R Programming](/rprog/)
-3. [Getting and Cleaning Data](/getclean/)
-4. [Exploratory Data Analysis](/eda/)
-5. [Reproducible Research](/repres/)
-6. [Statistical Inference](/statinf/)
-7. [Regression Models](/regmod/)
-8. [Practical Machine Learning](/pml/)
-9. [Developing Data Products](/ddp/)
+1. [The Data Scientist’s Toolbox](https://www.coursera.org/course/datascitoolbox)
+2. [R Programming](https://www.coursera.org/course/rprog)
+3. [Getting and Cleaning Data](https://www.coursera.org/course/getdata)
+4. [Exploratory Data Analysis](https://www.coursera.org/course/exdata)
+5. [Reproducible Research](https://www.coursera.org/course/repdata)
+6. [Statistical Inference](https://www.coursera.org/course/statinference)
+7. [Regression Models](https://www.coursera.org/course/regmods)
+8. [Practical Machine Learning](https://www.coursera.org/course/predmachlearn)
+9. [Developing Data Products](https://www.coursera.org/course/devdataprod)
 
 - [Other Resources](/other/)
-- [Curated Pages][Statistics Using R with Biological Examples](http://cran.r-project.org/doc/contrib/Seefeld_StatsRBio.pdf)
+- [Curated Pages](http://cran.r-project.org/doc/contrib/Seefeld_StatsRBio.pdf)