categorical variable的意思|示意

Categorical variables, also known as nominal variables, are variables that contain only descriptive values that cannot be logically ordered. Categorical variables also might have a limited number of values. They are mainly used when the data being collected has defined values and when the data is being used to classify information.

Categorical variables can take either a numerical or a non-numerical form. For example, a survey may ask the respondent to define their gender as either male or female. Here, gender is a categorical variable with two values (male or female). Alternatively, a survey may ask a respondent to rate how satisfied they are with a product on a scale of 1 to 5. Here, the satisfaction is a categorical variable using numerical values.

In many data analysis scenarios, categorical variables are often used to generate frequency distributions. A frequency distribution is a listing or a table of the number of times each value for a variable occurs. For example, a survey may ask the respondent to define their education level as either high school, college, or post graduate. Here, education level is a categorical variable. We can then create a frequency distribution table to show the number of respondents that have each level of education.

Categorical variables are also often used in regression analysis. This type of analysis allows us to examine the relationship between a dependent variable and one or more independent variables. In this example, we could look at how a dependent variable, such as income level, is affected by education level which is a categorical variable.

Categorical variables are a powerful tool for data analysis. They are frequently used in survey research, marketing research, public opinion polls, and regression analysis. They are also a key component in machine learning algorithms that involve natural language processing and classification tasks.

总结：

Categorical variable，又称为nominal variable，是指仅包含描述性的值，无法以逻辑顺序排列的变量，也可能有有限的值。它们主要用于收集有定义值的数据并用于分类信息。Categorical variable 可以采用数字或非数字形式，并可用于生成频率分布表，也可用于回归分析，是数据分析中功能强大的工具，在调查研究、市场调查、公众意见调查和回归分析中都有广泛应用，也是自然语言处理和分类任务中的关键部分。