tailieunhanh - Lecture Statistical techniques in business and economics (14/e): Chapter 9 - Lind, Marchal, Wathen

Chapter 9 - Estimation and confidence intervals. When you have completed this chapter, you will be able to: Define a point estimate, define level of confidence, construct a confidence interval for the population mean when the population standard deviation is known, construct a confidence interval for a population mean when the population standard deviation is unknown,. | Estimation and Confidence Intervals Chapter 9 GOALS Define a point estimate. Define level of confidence. Construct a confidence interval for the population mean when the population standard deviation is known. Construct a confidence interval for a population mean when the population standard deviation is unknown. Construct a confidence interval for a population proportion. Determine the sample size for attribute and variable sampling. Sampling and Estimates Why Use Sampling? To contact the entire population is too time consuming. The cost of studying all the items in the population is often too expensive. The sample results are usually adequate. Certain tests are destructive. Checking all the items is physically impossible. Point Estimate versus Confidence Interval Estimate A point estimate is a single value (point) derived from a sample and used to estimate a population value. A confidence interval estimate is a range of values constructed from sample data so that the . | Estimation and Confidence Intervals Chapter 9 GOALS Define a point estimate. Define level of confidence. Construct a confidence interval for the population mean when the population standard deviation is known. Construct a confidence interval for a population mean when the population standard deviation is unknown. Construct a confidence interval for a population proportion. Determine the sample size for attribute and variable sampling. Sampling and Estimates Why Use Sampling? To contact the entire population is too time consuming. The cost of studying all the items in the population is often too expensive. The sample results are usually adequate. Certain tests are destructive. Checking all the items is physically impossible. Point Estimate versus Confidence Interval Estimate A point estimate is a single value (point) derived from a sample and used to estimate a population value. A confidence interval estimate is a range of values constructed from sample data so that the population parameter is likely to occur within that range at a specified probability. The specified probability is called the level of confidence. What are the factors that determine the width of a confidence interval? sample size, n. variability in the population, usually σ estimated by s. desired level of confidence. Interval Estimates - Interpretation For a 95% confidence interval about 95% of the similarly constructed intervals will contain the parameter being estimated. Also 95% of the sample means for a specified sample size will lie within standard deviations of the hypothesized population How to Obtain z value for a Given Confidence Level The 95 percent confidence refers to the middle 95 percent of the observations. Therefore, the remaining 5 percent are equally divided between the two tails. Following is a portion of Appendix . Point Estimates and Confidence Intervals for a Mean – σ Known The width of the interval is determined by the level of .

• Kinh tế học
• Statistical techniques
• Statistical techniques in business
• Statistical techniques in economics
• Descriptive statistics
• Confidence intervals
• Level of confidence
• Statistical inference
• Independent samples
• Statistical process control
• Quality management
• Random observation
• Sampling methods
• Central limit theorem
• Point estimator
• Confidence interval
• Hypothesis testing
• Alternative hypothesis
• Analysis of variance
• F distribution
• Linear regression
• Coefficient of correlation
• Multiple regression
• Multiple regression analysis
• Chi square applications
• Test of hypothesis
• Analysis of ranked data
• Kruskal Wallis test
• Index numbers
• Consumer price index
• Time series
• Linear trend equation
• Decision making
• Organize information
• The role of statistics
• Qualitative variable
• Describing data
• Frequency distribution
• Central tendency
• Standard deviation
• Ungrouped data
• Probability concepts
• Random experiment
• Discrete probability distributions
• Continuous random variables
• Decision theory
• Decision alternative
• Inferential statistics
• Frequency tables
• Numerical measures