Normal distribution (3) When you don’t know the standard deviation.

Slides:



Advertisements
Similar presentations
The Normal Distribution
Advertisements

AP Statistics Chapter 7 – Random Variables. Random Variables Random Variable – A variable whose value is a numerical outcome of a random phenomenon. Discrete.
Statistics S2 Year 13 Mathematics. 17/04/2015 Unit 1 – The Normal Distribution The normal distribution is one of the most important distributions in statistics.
Normal Distributions: Finding Probabilities 1 Section 5.2.
The normal distribution
THE STANDARD NORMAL Unit 5, Day 3. Learning Goals for Today I can state the difference between a Normal Distribution and a Standard Normal Distribution.
Statistical Review for Chapters 3 and 4 ISE 327 Fall 2008 Slide 1 Continuous Probability Distributions Many continuous probability distributions, including:
Variance and Standard Deviation The Expected Value of a random variable gives the average value of the distribution The Standard Deviation shows how spread.
CSE 221: Probabilistic Analysis of Computer Systems Topics covered: Confidence intervals.
Standard Normal Distribution
UNR, MATH/STAT 352, Spring summands UNR, MATH/STAT 352, Spring 2007.
1 Confidence Intervals for Means. 2 When the sample size n< 30 case1-1. the underlying distribution is normal with known variance case1-2. the underlying.
1. Normal Curve 2. Normally Distributed Outcomes 3. Properties of Normal Curve 4. Standard Normal Curve 5. The Normal Distribution 6. Percentile 7. Probability.
Normal and Sampling Distributions A normal distribution is uniquely determined by its mean, , and variance,  2 The random variable Z = (X-  /  is.
© 2010 Pearson Education Inc.Goldstein/Schneider/Lay/Asmar, CALCULUS AND ITS APPLICATIONS, 12e – Slide 1 of 15 Chapter 12 Probability and Calculus.
7.2 Confidence Intervals When SD is unknown. The value of , when it is not known, must be estimated by using s, the standard deviation of the sample.
QBM117 Business Statistics Probability and Probability Distributions Continuous Probability Distributions 1.
Normal distribution (2) When it is not the standard normal distribution.
7.3 APPLICATIONS OF THE NORMAL DISTRIBUTION. PROBABILITIES We want to calculate probabilities and values for general normal probability distributions.
Hypothesis Testing for Variance and Standard Deviation
Example 9.6 Analyzing Variability in Diameters of Machine Parts Confidence Interval for a Standard Deviation.
The normal distribution Mini whiteboards – label with anything you know about the curve.
Module 13: Normal Distributions This module focuses on the normal distribution and how to use it. Reviewed 05 May 05/ MODULE 13.
7.4 – Sampling Distribution Statistic: a numerical descriptive measure of a sample Parameter: a numerical descriptive measure of a population.
Chapter 7: Introduction to Sampling Distributions Section 2: The Central Limit Theorem.
Starter The length of leaves on a tree are normally distributed with a mean of 14cm and a standard deviation of 4cm. Find the probability that a leaf is:
DISCRETE RANDOM VARIABLES.
The Standard Normal Distribution Section 5.2. The Standard Score The standard score, or z-score, represents the number of standard deviations a random.
§ 5.3 Normal Distributions: Finding Values. Probability and Normal Distributions If a random variable, x, is normally distributed, you can find the probability.
Statistics. A two-dimensional random variable with a uniform distribution.
Tarsia puzzle in groups of 3-4. Confidence intervals To calculate confidence intervals. To understand what a confidence interval is.
Probability Distributions A farmer grows sweet corn and each year sets aside one row of sweet corn for his local school. The farmer gives to the.
INTRODUCTORY MATHEMATICAL ANALYSIS For Business, Economics, and the Life and Social Sciences  2011 Pearson Education, Inc. Chapter 16 Continuous Random.
Chapter 7 The Normal Probability Distribution 7.3 Applications of the Normal Distribution.
6.4 Application of the Normal Distribution: Example 6.7: Reading assignment Example 6.8: Reading assignment Example 6.9: In an industrial process, the.
1 Sampling distributions The probability distribution of a statistic is called a sampling distribution. : the sampling distribution of the mean.
Honors Advanced Algebra Presentation 1-6. Vocabulary.
Unit 2 – Statistics Standard Deviation and Normal Distribution Mr. Solórzano – Algebra 2.
An Example of {AND, OR, Given that} Using a Normal Distribution By Henry Mesa.
THE NORMAL DISTRIBUTION Lesson 2. Starter: Find P (Z
Properties of Normal Distributions 1- The entire family of normal distribution is differentiated by its mean µ and its standard deviation σ. 2- The highest.
12.SPECIAL PROBABILITY DISTRIBUTIONS
Section 2 Standard Units and Areas under the Standard Normal Distribution.
Ch5.4 Central Limit Theorem
Chapter 7 The Normal Probability Distribution
Random Variables and Probability Distribution (2)
Lecture 5 Faten alamri.
5.2 Normal Distributions: Finding Probabilities
Sample Mean Distributions
Normal Distribution Many things closely follow a Normal Distribution:
AP Statistics: Chapter 7
Means and Variances of Random Variables
Chapter 9 Hypothesis Testing
An Example of {AND, OR, Given that} Using a Normal Distribution
عمل الطالبة : هايدى محمد عبد المنعم حسين
The Normal Probability Distribution Summary
Consider the following problem
Two-way analysis of variance (ANOVA)
Chapter 9 Hypothesis Testing
Sampling Distributions
Random WALK, BROWNIAN MOTION and SDEs
6.4 Application of the Normal Distribution:
Sampling Distribution of the Mean
Use the graph of the given normal distribution to identify μ and σ.
10-5 The normal distribution
The Normal Distribution
Combining Random Variables
An Example of {AND, OR, Given that} Using a Normal Distribution
Consider the following problem
Presentation transcript:

Normal distribution (3) When you don’t know the standard deviation

The Normal Distribution WRITTEN : … which means the continuous random variable X is normally distributed with mean  and variance  2 (standard deviation  )

Example: A machine produces components whose lengths are normally distributed with a mean of 20cm. Given that 8% of the components produced have a length greater than 20.5cm …. Find the standard deviation P(L>20.5)=8%=0.08

Example A machine produces components whose lengths are normally distributed with a mean of 20cm. Given that 8% of the components produced have a length greater than 20.5cm, find the standard deviation P(L>20.5)=8%=0.08 a P(Z>a)=0.08 P(Z<a)=0.92

Example contd… A machine produces components whose lengths are normally distributed with a mean of 20cm. Given that 8% of the components produced have a length greater than 20.5cm, find the standard deviation P(L>20.5)=8%=0.08 Use inverse normal distribution tables …... a =