# Cross-sectional and panel data analysis

### Econometrics: the difference between consolidated data and panel data

A, data characteristics are different

1, panel data is the “cross-section data” and “time series data” combined with a type of data. With a “cross-section” and “time series” of two dimensions, when this type of data arranged in two dimensions, the data are arranged in a plane, and arranged in a line with one-dimensional data have obvious differences, the entire form is like a panel.

2, merge data is the data in different data sources to collect, organize, clean, convert and load to a new data source.

Two, the meaning of the data is different

1, panel data is a cross-section of individuals at different points in time repeated measurements.

2, merged data is a process data of data collection and organization.

Three, data analysis methods are different

1, panel data in the analysis, more panel data model, which can be used to analyze the samples in the time series composed of the characteristics of the data, it is able to comprehensively utilize the sample information, through the parameters in the model, both to analyze the differences between the individuals, and also to describe the characteristics of the dynamic changes in individuals.

Baidu Encyclopedia – Merged Data (Data Integration)

### Summary of empirical research ideas based on panel data

1, quantitative analysis with empirical support and empirical testing;

2, obtaining cross-sectional data along with a certain time depth, establishing a standardized research model, and constructing a robust evaluation index system;

3, in terms of the selection of evaluation methods, the subjective evaluation In terms of the selection of evaluation methods, the subjective evaluation methods include TOPSIS, hierarchical analysis, cloud modeling and integer planning model, etc., while the objective evaluation methods include entropy weighting, correlation regression, factor analysis and data envelopment method, etc.;

4. Compared with the cross-section model and the time series model which only take into account the influence of a single dimension, the panel data combines both the cross-section and the time dimension, which can solve the problems that the cross-section and the time series data cannot solve individually;

5.

5. The panel data model can effectively solve the problem of omitted variables caused by unobservable individual differences or “heterogeneity” between objects, while the panel sample capacity has been greatly increased, which significantly improves the accuracy of estimation compared with the cross-section.

Research ideas related to competitiveness evaluation:

First, the construction of the indicator system (selection of appropriate evaluation indicators, key indicators with objectivity as well as horizontal and vertical comparability; evaluation methodology to assign values to the indicators; the formation of algorithms; evaluation; data analysis; modeling; analysis of the results; and draw conclusions).

### Is it meaningful that the panel data intercept term is significant

It is meaningful.

It is meaningful to analyze the smoothness of the data if the panel data intercept term is significant, because the panel data model needs to test the smoothness of the data before regression. Some non-smooth economic time series tend to show common trends, and there is not necessarily a direct correlation between the series themselves, when regression of these data is required.

Panel data, also known as parallel data, have two dimensions: time series and cross-section. When this type of data is arranged in two dimensions, it is arranged in a plane, with only one dimension of the data arranged in a line is significantly different, the whole table is like a panel, so it is called panel data.