Sampling distributions & estimators.html (2899B)
1 <?xml version="1.0" encoding="UTF-8"?> 2 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 3 <html><head><link rel="stylesheet" href="sitewide.css"><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"/><meta name="exporter-version" content="Evernote Mac 7.6 (457297)"/><meta name="altitude" content="-4.208069801330566"/><meta name="author" content="Alex Balgavy"/><meta name="created" content="2018-12-16 00:43:31 +0000"/><meta name="latitude" content="52.30035400390625"/><meta name="longitude" content="4.988170682800604"/><meta name="source" content="desktop.mac"/><meta name="updated" content="2018-12-16 01:27:55 +0000"/><title>Sampling distributions & estimators</title></head><body><h1>Sampling distributions & estimators</h1><div style="margin-top: 1em; margin-bottom: 1em;-en-paragraph:true;"><div>sampling distribution of sample mean: probability distribution of random variable 4 <img src="Sampling%20distributions%20&%20estimators.resources/552E86FD-22CC-4049-9704-493C7CC73AA5.png" height="16" width="19"/></div><div> 5 sampling distribution of sample proportion: probability distribution of 6 <img src="Sampling%20distributions%20&%20estimators.resources/02603FCF-F8A7-4685-ADDB-F61C740E6D5E.png" height="17" width="15"/></div></div><div style="margin-top: 1em; margin-bottom: 1em;-en-paragraph:true;">a sample proportion is 7 <img src="Sampling%20distributions%20&%20estimators.resources/F6E65F44-3F47-42A6-BF45-A777BA29888E.png" height="31" width="176"/></div><div style="margin-top: 1em; margin-bottom: 1em;-en-paragraph:true;"> 8 <img src="Sampling%20distributions%20&%20estimators.resources/C79EBBB9-CF36-42A1-AA47-922A5328AF6E.png" height="31" width="124"/>, with p the number of successes</div><h2>Confidence intervals</h2><div style="margin-top: 1em; margin-bottom: 1em;-en-paragraph:true;">a way to estimate stuff. e.g. a 95% confidence interval means we are 95% confident that this interval has a true value of 9 <img src="Sampling%20distributions%20&%20estimators.resources/46623A86-1281-4C69-A02B-E97D9AE1E158.png" height="11" width="8"/>.</div><div style="margin-top: 1em; margin-bottom: 1em;-en-paragraph:true;"><span style="font-size: 16px;"> 10 <img src="Sampling%20distributions%20&%20estimators.resources/94A94B8B-C601-4EEA-8405-1A493EA0DD51.png" height="35" width="109"/></span><br/></div><div style="margin-top: 1em; margin-bottom: 1em;-en-paragraph:true;"><div>Z is the Z-score for the confidence level you want (find this with a table).</div><div> 11 The margin of error is whatever you add to/subtract from the sample mean.</div><div> 12 To get 13 <img src="Sampling%20distributions%20&%20estimators.resources/B849CBF7-AC34-4B58-BABA-D4C32843ED83.png" height="10" width="13"/>, you can use the central limit theorem.</div></div><div><br/></div></body></html>