# Normal Distribution

Continuous distributions describe variables that take values from a continuous range and can be measured with any degree of accuracy. The commonest and the most useful continuous distribution is the normal distribution. The Normal Distribution is a symmetrical probability distribution where most results are located in the middle and few are spread on both sides. It has the shape of a bell and can entirely be described by its mean and standard deviation. Read more »

# Probability Distributions

Most improvement projects and scientific research studies are conducted with sample data rather than with data from an entire population. A Probability Distribution is a way to shape the sample data to make predictions and draw conclusions about an entire population. It refers to the frequency at which some events or experiments occur. It helps finding all the possible values a random variable can take between the minimum and maximum statistically possible values. Read more »

# Descriptive Statistics

Descriptive statistics are methods of describing the characteristics of a data set. It includes calculating things such as the average of the data, its spread and the shape it produces. It involves describing, summarizing and organizing the data so it can be easily understood. Graphical displays are often used along with the quantitative measures to enable clarity of communication. Descriptive statistics helps exploring and making conclusions about the data in order to make more rational decisions. Read more »

# Value Analysis

Value is one of the most important concepts within Lean thinking and one of the most valuable outcomes Lean provides. Value Analysis focuses on what adds value to business processes as perceived by the customer. A process that does not add value to the product or service should be redesigned or eliminated altogether. Problem solving and continuous improvement efforts often focus on those aspects of processes that add no value to the customer and are therefore wasteful. Read more »

# Waste Analysis

In a Lean culture, Waste is anything that doesn’t add value from the customer’s perspective. It includes activities and resources beyond what is needed to meet customer requirements. Waste Analysis involves identifying, quantifying, eliminating and preventing waste in manufacturing, service and office environments. Many Lean tools and techniques focus on continually identifying and eliminating these wastes to bring efficiency and effectiveness to existing processes, and this is one of the core principles of Lean thinking. Read more »

# Histograms and Boxplots

## Histograms:

A histogram is a graphical representation of a frequency distribution for numeric data. It is a bar chart that is often used as the first step to determine the probability distribution of a data set or a sample. It allows to visually and quickly assess the shape of the distribution, the central tendency, the amount of variation in the data, and the presence of gaps, outliers or unusual data points. Read more »

# Graphical Analysis

A long list of data is usually not practical for conveying information about a process. One of the best ways to analyze problems in any process is to plot the data and see what it is telling you. This is often recommended as a starting point in any data analysis during the problem-solving process. A wide range of graphical tools are available which can generate graphs quickly and easily such as Minitab and Microsoft Excel. Read more »

# Process Yield Measures

An ideal process must produce without defects and without rework. To expose these unnecessary and costly inefficiencies, you should have the appropriate performance metrics to measure the process yield, or otherwise, you may be misled and the true process yield might be underestimated. These metrics should be able to expose even the smallest inefficiencies in a process enabling operations to understand their true process yield in order to set realistic improvement targets. Read more »

# Kano Analysis

The Kano Model is a framework that is used to analyze customer needs and how those needs change as time goes on. It helps categorizing and prioritizing the different features of a product or service based on their impact to customer satisfaction. Those categories are then considered when analyzing potential opportunities for improvement. The Kano Model is often used to better understand how a product (or service) fits customer needs by mapping the existing or proposed features into the Kano categories. Read more »

# Key Performance Indicators (KPIs)

Performance management is an approach used to manage performance of an organization. It can play an important role in the success or failure of a business. It can be applied to measure the performance of an organization, a business unit, a single department, a project, an employee, and even the process to build a product or service. It includes activities that will help to ensure goals are consistently being met in an effective manner. Read more »

# Check Sheets

Check sheets are manual data collection forms used to collect data in real time at the location where the data is generated. They can be used on a temporary basis (for example during a project) or be established for routine activities. They enable faster capturing and compiling of data, allow the data to be recorded in a consistent manner, and enable capturing essential contextual and descriptive information that otherwise may be overlooked or forgotten. Read more »

# Gap Analysis

Gap Analysis compares two things, what is with what should be. It often helps comparing two different states of something, the current state and the future state. Once the gap is identified, an action plan can be developed to bridge the gap. Read more »