- 9.1: Carpal Tunnel Syndrome Carpal tunnel syndrome is a common wrist com...
- 9.2: Carpal Tunnel Syndrome Construct a confidence interval suitable for...
- 9.3: Airbags Save Lives In a study of the effectiveness of airbags in ca...
- 9.4: Are Flights Cheaper When Scheduled Earlier? Listed below are the co...
- 9.5: Self-Reported and Measured Female Heights As part of the National H...
- 9.6: Eyewitness accuracy of Police Does stress affect the recall ability...
- 9.7: Eyewitness accuracy of Police Construct a confidence interval suita...
- 9.8: Effect of Blinding Among 13,200 submitted abstracts that were blind...
- 9.9: Comparing Means The baseline characteristics of different treatment...
- 9.10: Comparing Means Repeat Exercise 9 by using a confidence interval in...
Solutions for Chapter 9: Inferences from Two Samples
Full solutions for Essentials of Statistics | 5th 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
A study in which a sample from a population is used to make inference to a future population. Stability needs to be assumed. See Enumerative study
An estimator for a parameter obtained from a Bayesian method that uses a prior distribution for the parameter along with the conditional distribution of the data given the parameter to obtain the posterior distribution of the parameter. The estimator is obtained from the posterior distribution.
An equation for a conditional probability such as PA B ( | ) in terms of the reverse conditional probability PB A ( | ).
A horizontal line on a control chart at the value that estimates the mean of the statistic plotted on the chart. See Control chart.
Central composite design (CCD)
A second-order response surface design in k variables consisting of a two-level factorial, 2k axial runs, and one or more center points. The two-level factorial portion of a CCD can be a fractional factorial design when k is large. The CCD is the most widely used design for itting a second-order model.
An experiment in which the treatments (experimental conditions) that are to be studied are included in the experiment. The data from the experiment are used to evaluate the treatments.
When a factorial experiment is run in blocks and the blocks are too small to contain a complete replicate of the experiment, one can run a fraction of the replicate in each block, but this results in losing information on some effects. These effects are linked with or confounded with the blocks. In general, when two factors are varied such that their individual effects cannot be determined separately, their effects are said to be confounded.
A correction factor used to improve the approximation to binomial probabilities from a normal distribution.
A method to derive the probability density function of the sum of two independent random variables from an integral (or sum) of probability density (or mass) functions.
A dimensionless measure of the linear association between two variables, usually lying in the interval from ?1 to +1, with zero indicating the absence of correlation (but not necessarily the independence of the two variables).
Used in statistical quality control, a defect is a particular type of nonconformance to speciications or requirements. Sometimes defects are classiied into types, such as appearance defects and functional defects.
Degrees of freedom.
The number of independent comparisons that can be made among the elements of a sample. The term is analogous to the number of degrees of freedom for an object in a dynamic system, which is the number of independent coordinates required to determine the motion of the object.
An experiment in which the tests are planned in advance and the plans usually incorporate statistical models. See Experiment
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.
Finite population correction factor
A term in the formula for the variance of a hypergeometric random variable.
Fixed factor (or fixed effect).
In analysis of variance, a factor or effect is considered ixed if all the levels of interest for that factor are included in the experiment. Conclusions are then valid about this set of levels only, although when the factor is quantitative, it is customary to it a model to the data for interpolating between these levels.
In statistical quality control, that portion of a number of units or the output of a process that is defective.
The geometric mean of a set of n positive data values is the nth root of the product of the data values; that is, g x i n i n = ( ) = / w 1 1 .
Geometric random variable
A discrete random variable that is the number of Bernoulli trials until a success occurs.