Econometrics may be defined as the social science in which the tools of economic theory, mathematics and statistical inference are applied to the analysis of economic phenomena.

(i) Regression means going back and it is a mathematical measure showing the average relationship between two variables.
(ii) It indicates the cause and effect relationship between the variables and establishes functional relationship.

(i) Correlation is a statistical device that helps to analyse the covariation of two or more variables.
(ii) Correlation is the relationship between two or more variables which vary with the other in the same or the opposite direction.

Central Statistical Office (CSO)
(i)  It is responsible for co-ordination of statistical activities in the country and for evolving and maintaining statistical standards.
(ii) It compiles National Accounts, conducts Annual Survey of Industries and Economic Census, compiles Index of Industrial Production and Consumer Price Indices.
(iii) It deals with social statistics, training, international co-operation, Industrial Classification, etc.
National Sample Survey
Organisation
NSSO has four divisions:
(i) Survey Design and Research Division
(ii) Field Operations. Division
(iii) Data Processing Division
(iv) Co-ordination and Publication Division
The Programme Implementation Wing has 3 Divisions:
(i) Twenty Point Programme
(ii) Infrastructure Monitoring and Project Monitoring
(iii) Member of Parliament Local Area Development Scheme.
1. There is National Statistical Commission and one autonomous Institute, i.e., Indian Statistical Institute.

(i) Models in Mathematical Economics are developed based on Economic Theories, while Econometric Models are developed based on Economic Theories to test the validity of Economic Theories in reality through the actual data.
(ii) Regression Analysis in Statistics does not concentrate more on error term while Econometric Models concentrate more on error terms  

(i) The general objective of Econometrics is to give empirical content to economic theory
(ii) The specific objectives are :
(i) It helps to explain the behaviour of a forthcoming period that is forecasting economic phenomena.
(ii)  It helps to prove the old and established relationships among the variables or between the variables.
(iii) It helps to establish new theories and new relationships.
(iv) It helps to test the hypotheses and estimation of the parameter.

Econometrics is the statistical and mathematical analysis of economic relationships, often serving as a basis for economic forecasting. It is used by economists to study relationships between economic variables Econometrics is interesting because it provides the tools to enable us to extract useful information about important economic policy issues from the available data. It is used to understand economic issues and test theories. Without evidence economic theories are abstract and has no bearing on reality. Econometrics is a set of tools we can use to confront theory with real world data. A study' could estimate a key parameter such as the price elasticity of demand for it or econometric techniques could be used to generate forecasts. It is used to develop, estimate and evaluate models which relate economic or financial variables.

S.NO.XYXYX²Y² 1 23 18 414 529 324 2 27 22 594 729 484 3 28 23 644 784 529 4 29 24 696 841 576 5 30 25 750 900 625 6 31 26 806 961 676 7 33 28 924 1089 784 8 35 29 1015 1225 841 9 36 30 1080 1296 900 10 39 32 1248 1521 1024 N=10 311 257 8171 9875 6763 \(r =\frac{N \sum X Y-\left(\sum X\right)\left(\sum Y\right)}{\sqrt{N \sum X^{2}-\left(\sum X\right)^{2}} \sqrt{N \sum Y^{2}-\left(\sum Y\right)^{2}}} \)
\(=\frac{(10 \times 8171)-311 \times 257}{\sqrt{(10 \times 9875)-(311)^{2}} \sqrt{10 \times 6763-(257)^{2}}} \)
\(=\frac{81710-79927}{\sqrt{98750-96721} \sqrt{67630-66049}} \)
\(=\frac{1783}{\sqrt{2029} \sqrt{1581}}=0.9955\)
Ans: + 0.9955 high correleated