prop_test: Proportion Test

In jrpriceUPS/Math160UPS: Suite of Functions for Math 160 Classes at the University of Puget Sound

Proportion Test

Description

This function asks you a sequence of questions in order to execute a proportion test. It finds a confidence interval and a p-value, produces a plot, and indicates how this could be queried directly from R.

Usage

prop_test()

Examples

> prop_test()
Do you have a single population or are you comparing populations?
  Possible answers are 'single' and 'comparing'.
single
How many trials were there in your experiment?
  10
How many successes were there?
  5
The statistics for your dataset are:
  phat = 0.5
s = sqrt(0.5*(1-0.5)/10) = 0.1581139

What is the theoretical proportion you are testing against (called p_0)?
  (If you only want a confidence interval, type 'NA')
.2
What is your desired confidence level?
  .9
The probability of getting this result or more extreme for phat
if the proportion really is 0.2 is
p =  0.0327935

The 90% confidence interval for the population proportion is
0.187086  < p <  0.812914


You can get this result by typing:
  binom.test(x = 5, n = 10, p = 0.2, alternative = 'two.sided', conf.level = 0.9)






> prop_test()
Do you have a single population or are you comparing populations?
  Possible answers are 'single' and 'comparing'.
comparing
How many trials were there in your first sample?
  15
How many successes were there in your first sample?
  10
How many trials were there in your second sample?
  20
How many successes were there in your second sample?
  10
The statistics for your dataset are:
  phat1 = 0.6666667
phat2 = 0.5
s = sqrt(0.6666667*(1-0.6666667)/15+0.5*(1-0.5)/20) = 0.1652719
What is your desired confidence level?
  .95
The probability of getting this result or more extreme for phat2 - phat1
if there really is no difference is
p =  0.521582

The 95% confidence interval for the difference in proportions is
-0.5489271  < p2 - p1 <  0.2155937


You can get this result by typing:
  prop.test(c(10,10), c(20,15), alternative = 'two.sided', conf.level = 0.95)

jrpriceUPS/Math160UPS documentation built on April 28, 2024, 12:41 p.m.