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+# rnblight
+
+Update markdown result chunks in markdown documents
+
+```bash
+cd /Users/brandl/Dropbox/projects/datautils/R/rnblight
+#cp /Users/brandl/Dropbox/documents/datascience/chi2.md rerender/
+#cp -r /Users/brandl/Dropbox/documents/datascience/.chi2_images rerender/
+#
+#git init
+#git add chi2.md
+#git commit -m "initial commit"
+
+mdInput=chi2.md
+mdBase=$(basename $mdInput .md)
+
+mv $mdInput ${mdBase}.Rmd
+
+Rscript - <<EOF
+knitr::knit('${mdBase}.Rmd', '${mdBase}.md')
+EOF
+
+idea .
+
+```
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+Frequency tests
+================
+
+* Example: Prop of dieting woman higher than for men?
+
+![](.example_images/fisher_example.png)
+
+```
+?fisher.test
+```
+
+
+Proportion Tests
+================
+
+```{r}
+prop.test(x=333, n=1022, conf.level=0.98)
+
+prop.test(x=333, n=1022)
+```
+
+From
+http://stats.stackexchange.com/questions/60073/confidence-interval-for-difference-between-proportions
+
+The sample size is 34, of which 19 are females and 15 are males. Therefore, the difference in proportions is 0.1176471.
+
+```{r}
+19/34 - 15/34
+prop.test(x=c(19,15), n=c(34,34), correct=FALSE)
+
+## also works for single proportion
+#prop.test(x=c(19), n=c(34), correct=FALSE)
+#prop.test(x=c(19,15,20), n=c(34,34,34), correct=FALSE)
+
+```
+Also see <http://stat.ethz.ch/R-manual/R-devel/library/stats/html/prop.test.html>
+
+Nice math introhttps://onlinecourses.science.psu.edu/statprogram/node/164 with t-statistc
+
+
+
+Confidence around proportions
+-----------------------------
+
+Formula:
+ > If the samples size n and population proportion p satisfy the condition that np ≥ 5 and n(1 − p) ≥ 5, than the end points of the interval estimate at (1 − α) confidence level is defined in terms of the sample proportion as follows.
+ ![](.example_images/prop_ci.png)
+
+CI math is detailed out under http://www.statisticslectures.com/topics/ciproportions/
+
+```{r}
+prop.test(x=333, n=1022, conf.level=0.98)
+plot(1:10)
+plot(1:10)
+prop.test(x=333, n=1022)
+plot(1:10)
+```
+