Download U1B L04 Normal Distributions 3p Class Notes .notebook

U1B L04 Normal Distributions 3p Class Notes .notebook
February 20, 2017
The Normal Distribution ­ a specific type of distribution
• symmetric
• single peaked
• bell­shaped
Sep 17­1:44 PM
• A normal curve is defined by its mean and standard deviation.
• Notation for a normal curve is N(μ, σ).
­3σ ­2σ
­σ
μ
+σ +2σ +3σ
Sep 17­1:49 PM
U1B L04 Normal Distributions 3p Class Notes .notebook
Label the normal curve below given:
N(100, 15)
Sep 17­1:49 PM
Label the normal curve below given:
N(64.5, 2.5)
μ
Sep 17­1:49 PM
February 20, 2017
U1B L04 Normal Distributions 3p Class Notes .notebook
February 20, 2017
May 25­9:26 AM
• Let's talk about where the data falls...
μ
• 50% falls below _______
• The majority of the data falls between ___ and ____
• In a normal curve, ______ of the data falls between ___ from the _____
• ___________ of the data falls between _____ from the ______
• ___________ of the data falls between _____ from the ______
• Color each of those regions on your normal distributions.
Sep 17­1:49 PM
U1B L04 Normal Distributions 3p Class Notes .notebook
February 20, 2017
• You try using the curve: N(64.5, 2.5)
μ
The heights of women aged 18 – 24 are approximately normally distributed with a mean μ = 64.5 inches and a standard deviation σ = 2.5 inches. • Between what two heights do the middle 95% fall?
• The tallest 2.5% of women are taller than what?
• What is the percentile for a woman who is 64.5 inches tall?
Sep 17­1:49 PM
• Label the normal curve below given: N(100, 15)
μ
• IQ scores on the WISC­IV are normally distributed with a mean of 100 and a standard deviation of 15.
• Going up one σ and down one σ from 100 gives us the range from 85 to 115. _____ of people have an IQ between 85 and 115.
• 95% of people have an IQ between ____ and ____.
• 99.7% of people have an IQ between ____ and ____.
Sep 17­1:49 PM
U1B L04 Normal Distributions 3p Class Notes .notebook
February 20, 2017
Put it all together!!! (draw and label the normal distribution, answer the questions)
• The army reports that the distribution of head circumference among male soldiers is approximately normal with mean 22.8 inches and standard deviation 1.1 inches.
• What percent of soldiers have a head circumference greater than 23.9 inches?
• What percentile is this?
• What percent of soldiers have a head circumference between 21.7 inches and 23.9 inches?
μ
Sep 17­1:52 PM
Feb 17­7:13 AM