Measures of Central Tendency
What is the mean?
The mean is the total of all observations divided by the number of observations
What is the standard deviation?
It measures the dispersion of data around the mean
What is the purpose of inferential statistics?
It generalizes findings from a sample to a population
How does central tendency relate to Six Sigma?
It helps analyze process performance and detect variation
What is an outlier?
An outlier is a data point significantly distant from other observations
How do you find the median?
Arrange the data in order, and the median is the middle value. If there is an even number of values, take the average of the two middle numbers
How do you calculate variance?
Variance is the square of the standard deviation
What distinguishes a population from a sample?
A population includes all units being studied, while a sample is a subset representing the population
Describe a statistical technique used in Six Sigma.
Control charts monitor process stability by identifying trends and deviations
What effect do outliers have on the mean?
Outliers can skew the mean, making it less representative of the dataset
What is the mode?
The mode is the most frequently occurring value in a dataset
What is the range?
The range is the difference between the maximum and minimum values in a dataset
Why is random sampling necessary?
It ensures the sample is representative of the population, reducing bias
How can histograms be used in process improvement?
They visualize data distribution and highlight areas for improvement
How can skewed data affect interpretation?
Skewed data can distort measures of central tendency and lead to incorrect conclusions
What are the measures of central tendency?
They include the mean, median, and mode, which describe the center of a dataset
What is dispersion?
Dispersion refers to the spread or variability of data within a dataset
What is a parameter?
A parameter is a numerical property describing a population
What is the role of control charts?
They track process variations over time and signal when corrective actions are needed
Give an example of skewed data.
Income distributions are often positively skewed, with most values clustering at lower levels
What is descriptive statistics?
Descriptive statistics summarize and describe data collected from experiments or surveys without generalizing beyond the data
What are descriptive statistics?
Descriptive statistics include numerical measures like mean, median, and range that summarize a dataset
Define sample data.
Sample data are observations collected from a subset of the population
What is the purpose of using statistics in Six Sigma?
Statistics identify and reduce process variability to improve quality
How can you identify an outlier?
Outliers can be identified as values significantly deviating from the dataset's range