Expected Value
![Picture](/uploads/1/6/6/0/16603678/137636039.png)
Practice: https://www.khanacademy.org/math/probability/random-variables-topic/expected-value/e/expected_value
Explanation: http://www.wikihow.com/Calculate-an-Expected-Value
Explanation: http://www.wikihow.com/Calculate-an-Expected-Value
Z-Scores
Things you
need to know in order to determine a z-score:
1. Mean
2. Standard deviation
3. The test point (the number you’re actually calculating the z-score for)
Z= (test point – mean) / standard deviation
Tip: sometimes you’re given the variance but not the standard deviation…. Ask yourself, how can you get from the variance to the deviation?? Hint: it’s super easy! If you can’t figure it out, email or text me!
How to find the area between z-scores: http://statistics.about.com/od/HelpandTutorials/ss/How-To-Calculate-Probabilities-With-A-Standard-Normal-Distribution-Table_6.htm
Z-Score Chart: http://www.regentsprep.org/Regents/math/algtrig/ATS7/ZChart.htm
1. Mean
2. Standard deviation
3. The test point (the number you’re actually calculating the z-score for)
Z= (test point – mean) / standard deviation
Tip: sometimes you’re given the variance but not the standard deviation…. Ask yourself, how can you get from the variance to the deviation?? Hint: it’s super easy! If you can’t figure it out, email or text me!
How to find the area between z-scores: http://statistics.about.com/od/HelpandTutorials/ss/How-To-Calculate-Probabilities-With-A-Standard-Normal-Distribution-Table_6.htm
Z-Score Chart: http://www.regentsprep.org/Regents/math/algtrig/ATS7/ZChart.htm