---
title: "Inference for means"
date: "10/??/2017"
output: html_document
---

```{r setup, include=FALSE}
knitr::opts_chunk$set(echo = TRUE)
```

## Example

Returning to the Peachtree Road Race example from before, let's compute a 95\% confidence 
interval for the *actual* overall mean.

```{r}
set.seed(1)
df = read.csv('https://www.marksmath.org/data/peach_tree2015.csv')
samp = sample(df$Net.Time, 100)
m = mean(samp)
s = sd(samp)
se = s/10
c(m,se, m-2*se, m+2*se)
```
