There are two forms of statistical data expression: statistical grid and statistical map. According to the representation method, it is divided into: ① partition statistics. That is, the area of a figure or the number of the same figure represents the sum of all similar phenomena in the division unit; For example, in 2008, the data sample files of American community survey for one year were classified as a whole.
There are: classified data, sorted data, fixed distance data, and fixed proportional variables. Statistics is a comprehensive science that infers the nature of the measured object and even predicts its future by searching, sorting, analyzing and describing the data.
In statistics, statistical data can be mainly divided into four types, namely classified data, ordinal data, fixed distance data and fixed ratio variables.
According to the measurement level reflected by the data, the data can be divided into four types: nominal data, sequential data, equidistant data and ratio data.
Briefly describe the definition of continuous data processing capability index.
1, indicators of process capability index: Cp, Cpk process capability index Cp, Cpk refers to the short-term capability of the process. Cp refers to the ability of the process to meet the technical requirements, which is usually expressed by dividing the deviation range of customer satisfaction by six six sigma.
2. For example, the intensity of the stimulation current can be continuously changed and measured. But if you divide your emotions into several levels: particularly unhappy, unhappy, average, happy and cheerful, these levels are not continuous quantities, but discrete quantities and discontinuous data.
3. Process capability analysis is inseparable from the knowledge of normal distribution. Let's start with histogram and normal distribution.
4. Process capability is generally measured by process capability index, as follows: (Double-sided specification) In which: tolerance is the upper limit of tolerance, the lower limit of tolerance, the standard deviation of the whole quality characteristic value, and the estimated value can be estimated according to the national standard GB/T409 1-200 1 (see or (see control chart).
5.CPK refers to the actual processing capacity of the process in a controlled state (steady state) within a certain period of time. It is the inherent ability of the process, or the ability of the process to ensure quality.
What is the meaning of continuous variables?
1, continuous variables and discrete variables are a pair of corresponding concepts. A continuous variable means that any point can be taken within the range of this variable, while a discrete variable can only take some points.
2. Continuous variables: continuous variables are always superimposed, and the growth can be divided into fixed units. Different discrete variables in the definition domain: the definition domain of discrete variables (that is, the set s of objects) is discrete. Continuous variable: the domain of a continuous variable (that is, the set s of objects) is continuous.
3. Continuous random variable: A continuous random variable refers to a random variable that takes any point in an interval on the number axis when all possible values of the random variable X cannot be enumerated one by one. Discrete random variables with different characteristics: variables can only take discrete natural numbers, which is a discrete random variable.
4. Continuous variables generally refer to continuous random variables. Continuous random variable refers to a random variable that takes any point in an interval on the number axis when all possible values of random variable X cannot be enumerated one by one. Discontinuous variables, if ordered, can be described by frequency or grouping statistics.
What is continuous data? What is discrete data? Second, what's the difference?
1, discrete data is also called discontinuous data, and the number of such data between any two data points is limited. For example, there are ten classes in a grade, and the number of classes here is discrete data (for example, there must be only nine classes between class eight and class ten, and this division is limited).
2. The difference between discrete and continuous variables is as follows: discrete variables are obtained in different ways: discrete variables are obtained by counting, that is, counting the objects to be counted, and the growth amount is not fixed. Continuous variables: continuous variables are always superimposed, and growth can be divided into fixed units.
3, continuous data, statistical concept, also known as continuous variables, refers to the data that can be taken arbitrarily in a certain interval, the value is continuous, and two adjacent values can be divided by infinity.
4. The difference between the two: discrete mathematics is relative to continuous mathematics, which is mainly based on whether the research object has continuity. From this perspective, ordinary calculus is continuous mathematics.
What do discrete random variables and continuous random variables mean respectively? What is the difference?
Discrete variables are obtained in different ways: discrete variables are obtained by counting, that is, counting the objects to be counted, and the growth amount is not fixed. Continuous variables: continuous variables are always superimposed, and growth can be divided into fixed units.
Continuous variables generally refer to continuous random variables. Continuous random variable refers to a random variable that takes any point in an interval on the number axis when all possible values of random variable X cannot be enumerated one by one. For example, the life of a batch of electronic components, the measurement errors often encountered in practice are continuous random variables.
A discrete variable refers to a variable whose value can be obtained by counting. On the other hand, continuous variables are random variables to measure something. Discrete variables take independent values, and continuous variables take arbitrary values within a given range or continuum. Discrete variables can be represented by isolated points.