- 8-5.1: Using Table G, find the critical value(s) for each, show the critic...
- 8-5.2: (ans) Using Table G, find the P-value interval for each x2 test val...
- 8-5.3: Calories in Pancake Syrup A nutritionist claims that the standard d...
- 8-5.4: High Temperatures in January Daily weather observations for southwe...
- 8-5.5: Stolen Aircraft Test the claim that the standard deviation of the n...
- 8-5.6: Carbohydrates in Fast Foods The number of carbohydrates found in a ...
- 8-5.7: Transferring Phone Calls The manager of a large company claims that...
- 8-5.8: Soda Bottle Content A machine fills 12-ounce bottles with soda. For...
- 8-5.9: High-Potassium Foods Potassium is important to good health in keepi...
- 8-5.10: Exam Grades A statistics professor is used to having a variance in ...
- 8-5.11: Tornado Deaths A researcher claims that the standard deviation of t...
- 8-5.12: Interstate Speeds It has been reported that the standard deviation ...
- 8-5.13: College Room and Board Costs Room and board fees for a random sampl...
- 8-5.14: Heights of Volcanoes A sample of heights (in feet) of active volcan...
- 8-5.15: Manufactured Machine Parts A manufacturing process produces machine...
Solutions for Chapter 8-5: x2 Test for a Variance or Standard Deviation
Full solutions for Elementary Statistics: A Step by Step Approach 8th ed. | 8th Edition
All possible (subsets) regressions
A method of variable selection in regression that examines all possible subsets of the candidate regressor variables. Eficient computer algorithms have been developed for implementing all possible regressions
In statistical hypothesis testing, this is a hypothesis other than the one that is being tested. The alternative hypothesis contains feasible conditions, whereas the null hypothesis speciies conditions that are under test
Axioms of probability
A set of rules that probabilities deined on a sample space must follow. See Probability
Chi-square (or chi-squared) random variable
A continuous random variable that results from the sum of squares of independent standard normal random variables. It is a special case of a gamma random variable.
Coeficient of determination
See R 2 .
An estimator that converges in probability to the true value of the estimated parameter as the sample size increases.
A square matrix that contains the variances and covariances among a set of random variables, say, X1 , X X 2 k , , … . The main diagonal elements of the matrix are the variances of the random variables and the off-diagonal elements are the covariances between Xi and Xj . Also called the variance-covariance matrix. When the random variables are standardized to have unit variances, the covariance matrix becomes the correlation matrix.
Another name for factors that are arranged in a factorial experiment.
Cumulative distribution function
For a random variable X, the function of X deined as PX x ( ) ? that is used to specify the probability distribution.
Defect concentration diagram
A quality tool that graphically shows the location of defects on a part or in a process.
W. Edwards Deming (1900–1993) was a leader in the use of statistical quality control.
Another name for a probability density function
Discrete random variable
A random variable with a inite (or countably ininite) range.
Distribution free method(s)
Any method of inference (hypothesis testing or conidence interval construction) that does not depend on the form of the underlying distribution of the observations. Sometimes called nonparametric method(s).
Erlang random variable
A continuous random variable that is the sum of a ixed number of independent, exponential random variables.
Estimate (or point estimate)
The numerical value of a point estimator.
Extra sum of squares method
A method used in regression analysis to conduct a hypothesis test for the additional contribution of one or more variables to a model.
A type of experimental design in which every level of one factor is tested in combination with every level of another factor. In general, in a factorial experiment, all possible combinations of factor levels are tested.
A model that contains only irstorder terms. For example, the irst-order response surface model in two variables is y xx = + ?? ? ? 0 11 2 2 + + . A irst-order model is also called a main effects model
A function that is used to determine properties of the probability distribution of a random variable. See Moment-generating function