- 7-1.1: How will you decide on a reasonable number of Kleenexes to put in t...
- 7-1.2: When do people usually need Kleenexes?
- 7-1.3: What type of data collection technique would you use?
- 7-1.4: Assume you found out that from your sample of 85 people, on average...
- 7-1.5: Explain how you decided how many Kleenexes will go in the boxes.
- 7-1.6: What statistic best estimates m?
- 7-1.7: What is necessary to determine the sample size?
- 7-1.8: In determining the sample size for a confidence interval, is the si...
- 7-1.9: Find each. a. za2 for the 99% confidence interval b. za2 for the 98...
- 7-1.10: Number of Faculty The numbers of faculty at 32 randomly selected st...
- 7-1.11: Reading Scores A sample of the reading scores of 35 fifth-graders h...
- 7-1.12: Freshmens GPA First-semester GPAs for a random selection of freshme...
- 7-1.13: Workers Distractions A recent study showed that the modern working ...
- 7-1.14: Golf Averages A study of 35 golfers showed that their average score...
- 7-1.15: Actuary Exams A survey of 35 individuals who passed the seven exams...
- 7-1.16: Number of Farms A random sample of the number of farms (in thousand...
- 7-1.17: Television Viewing A study of 415 kindergarten students showed that...
- 7-1.18: Day Care Tuition A random sample of 50 four-year-olds attending day...
- 7-1.19: Hospital Noise Levels Noise levels at various area urban hospitals ...
- 7-1.20: Length of Growing Seasons The growing seasons for a random sample o...
- 7-1.21: Time on Homework A university dean of students wishes to estimate t...
- 7-1.22: In the hospital study cited in Exercise 19, the mean noise level in...
- 7-1.23: Chocolate Chips per Cookie It is desired to estimate the mean numbe...
- 7-1.24: Cost of Pizzas A pizza shop owner wishes to find the 95% confidence...
- 7-1.25: National Accounting Examination If the variance of a national accou...
- 7-1.26: Commuting Times in New York The 90% confidence interval for the mea...
Solutions for Chapter 7-1: Confidence Intervals and Sample Size
Full solutions for Elementary Statistics: A Step by Step Approach | 7th Edition
a-error (or a-risk)
In hypothesis testing, an error incurred by failing to reject a null hypothesis when it is actually false (also called a type II error).
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
Bivariate normal distribution
The joint distribution of two normal random variables
Any test of signiicance based on the chi-square distribution. The most common chi-square tests are (1) testing hypotheses about the variance or standard deviation of a normal distribution and (2) testing goodness of it of a theoretical distribution to sample data
The mean of the conditional probability distribution of a random variable.
A probability distribution for a continuous random variable.
In the most general usage, a measure of the interdependence among data. The concept may include more than two variables. The term is most commonly used in a narrow sense to express the relationship between quantitative variables or ranks.
W. Edwards Deming (1900–1993) was a leader in the use of statistical quality control.
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).
Another name for a cumulative distribution function.
A concept in parameter estimation that uses the variances of different estimators; essentially, an estimator is more eficient than another estimator if it has smaller variance. When estimators are biased, the concept requires modiication.
A model to relate a response to one or more regressors or factors that is developed from data obtained from the system.
Error of estimation
The difference between an estimated value and the true value.
The expected value of a random variable X is its long-term average or mean value. In the continuous case, the expected value of X is E X xf x dx ( ) = ?? ( ) ? ? where f ( ) x is the density function of the random variable X.
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
Fisher’s least signiicant difference (LSD) method
A series of pair-wise hypothesis tests of treatment means in an experiment to determine which means differ.
Fraction defective control chart
See P chart
Gamma random variable
A random variable that generalizes an Erlang random variable to noninteger values of the parameter r
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 .