Class 11-commerce TR JAIN AND VK OHRI Solutions Statistics for Economics Chapter 1 - Concept of Economics and Significance of Statistics in Economics

1. Statistics means quantitative information.

It deals with quantitative information only and does not take qualitative data into consideration. Qualitative variables such as beauty, honesty and kindness cannot be studied.

2. Statistics and economics are complementary to each other.

Statistics plays a significant role in Economics. It

• Expresses economic problems quantitatively.
• Facilitates inter-sectoral and inter-temporal comparison.
• Helps in studying the cause and effect relationship between different economic variables which leads to construction of economic theories.

3. The term population refers to the aggregate of all items relating to statistical study. Thus, if statistical study comprises 200 items, then population is 200.
4. Descriptive statistics means those methods which are used for collection, presentation and analysis of data. Under this,  following estimations are done:

• Measurement of central tendencies such as mean, median, mode, quartiles, deciles and percentiles
• Measurement of dispersion such as range, quartile deviation, mean deviation and standard deviation
• Measurement of correlation through a scatter diagram and correlation coefficient. 

List of statistical information which will be required to facilitate comparison of academic performance of my school with the other schools in my neighbourhood: 

1. Data of the total number of schools and the total number of students in each school
2. Average marks obtained by students in each class in each school
3. Average marks of all students in each school
4. Coefficient of variation of marks

Academic performance of a school is better when average marks are highest and coefficient of variation is lowest.

Statistical variables which show cause and effect relationship with each other:

1. Price of a commodity and quantity supplied: Price of a commodity and quantity supplied are positively related to each other. That is, when the price of the commodity increases, more units of a commodity are supplied by the producer in the market and vice versa.
2. Price of a commodity and quantity demanded: Price of a commodity and quantity demanded are negatively related to each other. That is, when price of the commodity increases, less units of a commodity are demanded by the consumer and vice versa.