What are endogenous and exogenous variables?

An endogenous variable is a random variable with some probability distribution, the value of which is determined within the model of the economic system under study, and its parameters are the elements estimated by the simultaneous equation model. Endogenous variables are determined by and have an impact on the model system. Endogenous variables are generally economic variables.

Exogenous variables are generally deterministic variables, or random variables with critical probability distributions, whose values are determined outside the model of the economic system under study, and whose parameters are not elements studied by the model system. Exogenous variables affect the system but are not affected by the system. Exogenous variables are generally economic variables, conditional variables, policy variables, and virtual variables.

Endogenous variables are variables that change by themselves under the influence of pure economic factors within the economic system, and are usually not affected by policy factors, such as market economy, interest rates, exchange rates and other variables. Exogenous variables are variables that are affected by external factors, mainly policy factors, rather than internal factors in the economic system. Rate.

Whether the money supply is endogenous or exogenous involves an important issue, that is, whether the bank can effectively regulate the amount of money through the implementation of monetary policy, and whether it can effectively intervene in the economy. In fact, it is difficult to simply say whether the money supply is an endogenous variable or an exogenous variable. The money supply is both endogenous and exogenous.

The base currency is put by the central bank, the money multiplier is subject to the central bank's macroeconomic control, the amount of money is affected by the monetary policy to a certain extent, and the money supply is exogenous; However, the amount of money will also be affected by the behavior of other economic agents in the economic system, and the economic factors of investment, income, savings, and consumption make it difficult for banks to absolutely control the money supply. Therefore, the money supply has both endogenous and exogenous natures.

The difference between exogenous and endogenous variables is:First, the subject is different.

1. Endogenous variables: refer to the variables that the model wants to determine the denier base. It can be explained in the model system.

2. Exogenous variables: variables determined by the external mining bureau of the economic system and entered into the system, which cannot be explained in the model system.

Second, the characteristics are different.

1. Endogenous variables: have a certain probability distribution.

The parameters of the random variables are the elements estimated by the simultaneous equation system.

2. Exogenous variables: Variables that can affect endogenous variables, but it itself is determined by external factors that are constantly studied by economic models. Such variables can often be controlled by policy and used as a variable to achieve its policy objectives.

Third, the rules are different.

1. Endogenous variables: determined by the model system.

2. Exogenous variables: only have an impact on the system and are not affected by the system.

Endogenous variables are the variables that the model family makes decisions about.

Analysis: An independent variable of a model.

The dependent variables are endogenous variables, which are variables to be explained in a theory, and are determined by the model, for example, in the demand curve of economics, ** and the demand are endogenous to silver losses. Blade God.

For the simultaneous equation model system, it is no longer possible to divide the variables by the explanatory variables and the explanatory variables, but the variables are divided into two categories: endogenous variables and exogenous variables, and the endogenous variables have a certain probability distribution.

The parameters of the random variable are the elements estimated by the simultaneous equation system, and the endogenous variables are determined by the model system.

Endogenous explanatory variables.

1. The conditional zero mean assumption of the random error term implies that it does not depend on the change of x, and the assumption suggests that there is no correlation of any kind with x.

2. The conditional zero-mean assumption of the random error term implies that it varies independently of the change in x, and the assumption indicates that there is no correlation of any kind with x.

When this hypothesis is true, it also means that x is an endogenous explanatory variable.

Any system (or model) is made up of various variables, and when we analyze these systems (or models), we can choose to study the effects of some of these variables on others, then these variables we choose are called independent variables, and the amount of influence is called dependent variables.

In an economic model, endogenous variables are the variables that the model is going to determine. Exogenous variables are known variables that are determined by factors other than the model, and are the external conditions on which the model is based. Endogenous variables can be accounted for in the model system, exogenous variables determine endogenous variables, and exogenous variables themselves cannot be accounted for in the model system.

Parameters are often determined by factors other than the model and are therefore often seen as exogenous variables.

For example: p=a+bq, which means the relationship between ** and quantity, then a and b are parameters, both of which are exogenous variables; p and q are the variables to be determined by the model, so they are endogenous variables. In addition, other variables related to the model, such as the ** of related commodities and people's income, are exogenous variables.

Whereas q varies with p. q is the dependent variable and p is the independent variable.

In a model, exogenous variables cannot be independent and dependent variables, and endogenous variables are either independent or dependent variables.

Endogenous variables refer to the variables that are determined by the given economic model itself in an economic model.

Exogenous variables are variables that cannot be determined by a given economic model on its own, but are determined by factors other than this model. It is the external condition on which the model is built.

Endogenous variables can be accounted for within the model, exogenous variables determine endogenous variables, and exogenous variables cannot be accounted for within the model.

Exogenous variables are independent variables that are not affected by other variables in a study.

Extension: In other words, exogenous variables are variables that do not change with the change of the dependent variable and are often seen as factors beyond the control of the researcher. The opposite is endogenous variables, which are influenced by other variables in the causal relationship.

In the social sciences, exogenous hypersalience is often used to explain non-causally related variations in order to derive more accurate causal effects.

For example, in the study of economics, a person's income is the result of his or her education, work experience, etc., so these variables are all considered endogenous. Policies, global economic conditions, etc., are considered exogenous variables because they are usually not influenced by individual factors. In statistical analysis, researchers need to identify and control endogenous variables in order to better understand causality and reduce biases.

At the same time, exogenous variables can also be used for factors that are not considered in the Qilingkong explanatory model and improve the accuracy of **.

The endogenous variables are explained as follows:Example: p=a+bq, which indicates the relationship between ** and quantity, then a and b are parameters, both of which are exogenous variables; p and q are the variables to be determined by the model, so they are endogenous variables.

In addition, other variables related to the model, such as the ** of related commodities and people's income, are exogenous variables.

The independent variables and dependent variables of another model are endogenous variables, which are "variables to be explained in a theory", and they are all determined by the model. For example, in the demand curve of economics, ** and demand are both endogenous variables.

For the simultaneous equation model system, it is no longer possible to divide the variables by using the explanatory variables and the explanatory variables, but the variables can be divided into two categories: endogenous variables and exogenous variables. An endogenous variable is a random variable with some probability distribution, and its parameters are the elements estimated by the simultaneous equation system. Endogenous variables are determined by the model system.