Ordinal scales are valuable when it is difficult or impractical to establish exact numerical measurements, but you still want to capture respondents' preferences or perceptions in a ranked order. They provide valuable insights into the relative ranking or preference of items without requiring respondents to assign specific numerical values. However, when it comes to performing statistical analyses, ordinal data has limitations, as it lacks equal intervals between categories, and arithmetic operations like addition or subtraction are not meaningful. Therefore, it's crucial to use appropriate statistical methods when working with ordinal data.
Descriptive statistics are the statistics that summarize and describe the main features of a population or a dataset. They provide a concise and meaningful way to understand the central tendencies, variability, and distribution of the data.
For a normal distribution, approximately 95% of the total population falls within two standard deviations on each side of the mean. This is known as the "Empirical Rule" or the "68-95-99.7 Rule," which is a statistical rule of thumb that applies to data that follows a normal distribution.
Process Decision Program Chart (PDPC) is a tool primarily used in the planning phase of a project or implementation plan. Its purpose is to identify potential events or problems that may occur during the execution of a plan and to develop corresponding contingencies to address those events.
Statistical Process Control (SPC) is best defined as the use of statistical methods to understand and control a process. SPC is a powerful quality management technique that involves monitoring and analyzing process data to ensure that the process is stable, predictable, and capable of producing products or services that meet specified quality standards.
I & mR control charts are a type of control chart used in statistical process control (SPC) to monitor processes over time. They are particularly suitable for monitoring processes where individual data points are collected, rather than continuous data. Attribute data consists of data that can be categorized into discrete categories or counted, such as pass/fail, yes/no, or the number of defects in a sample.
The capability index is a statistical measure that assesses the ability of a process to produce products or services within specified limits. It compares the spread of process variation to the allowed tolerance limits.
DPU (Defects Per Unit) is a measure used to show the ratio of defects to units in a process. It is a key performance metric in quality management and process improvement efforts.
In a flowchart, oval shapes are typically used to represent the starting point or the termination point of a process or decision.
