Introduction to Statistics
ЁЯУР Formula & Cheat Sheet (English)
Quick Revision Notes: Class 11 Economics
Chapter: Introduction to Statistics (рд╕рд╛рдВрдЦреНрдпрд┐рдХреА рдХрд╛ рдкрд░рд┐рдЪрдп)
1. What is Economics? (рдЕрд░реНрдерд╢рд╛рд╕реНрддреНрд░ рдХреНрдпрд╛ рд╣реИ?)
Economics is a study of how people and society choose to employ scarce resources to produce various commodities over time and distribute them for consumption among various persons and groups in society.
- Consumer (рдЙрдкрднреЛрдХреНрддрд╛): A person who consumes goods and services for the satisfaction of wants.
- Producer (рдЙрддреНрдкрд╛рджрдХ): A person who produces goods and services for the generation of income.
- Service Holder (рд╕реЗрд╡рд╛ рдкреНрд░рджрд╛рддрд╛/рдзрд╛рд░рдХ): A person who is in service and gets paid for it (e.g., working in an office).
- Service Provider (рд╕реЗрд╡рд╛ рдкреНрд░рджрд╛рддрд╛): A person who provides services to others for a consideration (e.g., lawyer, doctor).
2. Meaning of Statistics (рд╕рд╛рдВрдЦреНрдпрд┐рдХреА рдХрд╛ рдЕрд░реНрде)
Statistics can be understood in two senses:
A. Plural Sense (рдмрд╣реБрд╡рдЪрди рд░реВрдк рдореЗрдВ - Numerical Data)
Statistics refers to numerical facts or data collected in a systematic manner for a specific purpose.
- Key Features:
- Aggregate of facts (рддрдереНрдпреЛрдВ рдХрд╛ рд╕рдореВрд╣)
- Numerically expressed (рд╕рдВрдЦреНрдпрд╛рддреНрдордХ рд░реВрдк рдореЗрдВ рд╡реНрдпрдХреНрдд)
- Affected by a multiplicity of causes (рдЕрдиреЗрдХ рдХрд╛рд░рдгреЛрдВ рд╕реЗ рдкреНрд░рднрд╛рд╡рд┐рдд)
- Placed in relation to each other (рдПрдХ-рджреВрд╕рд░реЗ рдХреЗ рд╕рдВрдмрдВрдз рдореЗрдВ)
- Pre-determined purpose (рдкреВрд░реНрд╡рдирд┐рд░реНрдзрд╛рд░рд┐рдд рдЙрджреНрджреЗрд╢реНрдп)
- Collected in a systematic manner (рд╡реНрдпрд╡рд╕реНрдерд┐рдд рдврдВрдЧ рд╕реЗ рд╕рдВрдХрд▓рд┐рдд)
B. Singular Sense (рдПрдХрд╡рдЪрди рд░реВрдк рдореЗрдВ - Statistical Methods)
Statistics refers to the statistical methods or techniques relating to collection, organization, presentation, analysis, and interpretation of data.
- Five Stages of Statistical Study (рд╕рд╛рдВрдЦреНрдпрд┐рдХреАрдп рдЕрдзреНрдпрдпрди рдХреЗ рдкрд╛рдБрдЪ рдЪрд░рдг):
- Collection of Data (рдЖрдБрдХрдбрд╝реЛрдВ рдХрд╛ рд╕рдВрдХрд▓рди)
- Organization of Data (рдЖрдБрдХрдбрд╝реЛрдВ рдХрд╛ рд╕рдВрдЧрдарди)
- Presentation of Data (рдЖрдБрдХрдбрд╝реЛрдВ рдХрд╛ рдкреНрд░рд╕реНрддреБрддреАрдХрд░рдг)
- Analysis of Data (рдЖрдБрдХрдбрд╝реЛрдВ рдХрд╛ рд╡рд┐рд╢реНрд▓реЗрд╖рдг)
- Interpretation of Data (рдЖрдБрдХрдбрд╝реЛрдВ рдХрд╛ рдирд┐рд░реНрд╡рдЪрди/рдирд┐рд╖реНрдХрд░реНрд╖)
3. Importance and Functions of Statistics (рд╕рд╛рдВрдЦреНрдпрд┐рдХреА рдХрд╛ рдорд╣рддреНрд╡ рдФрд░ рдХрд╛рд░реНрдп)
- Quantitative expression of economic problems (рдЖрд░реНрдерд┐рдХ рд╕рдорд╕реНрдпрд╛рдУрдВ рдХрд╛ рдорд╛рддреНрд░рд╛рддреНрдордХ рдЕрднрд┐рд╡реНрдпрдХреНрддрд┐).
- Inter-sectoral and inter-temporal comparison (рдХреНрд╖реЗрддреНрд░реАрдп рдФрд░ рдХрд╛рд▓рд┐рдХ рддреБрд▓рдирд╛).
- Working out cause and effect relationships (рдХрд╛рд░рдг рдФрд░ рдкреНрд░рднрд╛рд╡ рд╕рдВрдмрдВрдзреЛрдВ рдХреЛ рдЬреНрдЮрд╛рдд рдХрд░рдирд╛).
- Construction of economic theories and models (рдЖрд░реНрдерд┐рдХ рд╕рд┐рджреНрдзрд╛рдВрддреЛрдВ рдФрд░ рдореЙрдбрд▓реЛрдВ рдХрд╛ рдирд┐рд░реНрдорд╛рдг).
- Forecasting and policy formulation (рдкреВрд░реНрд╡рд╛рдиреБ┘Е╪з┘Ж рдФрд░ рдиреАрддрд┐ рдирд┐рд░реНрдорд╛рдг).
4. Limitations of Statistics (рд╕рд╛рдВрдЦреНрдпрд┐рдХреА рдХреА рд╕реАрдорд╛рдПрдБ)
- Study of numerical facts only: It does not study qualitative aspects (like honesty, poverty, beauty).
- Study of aggregates only: It does not study a single individual/observation.
- Homogeneity of data: Data must be comparable.
- Results are true on average: Statistical results are not universally true; they are true only under certain conditions.
- Can be misused: Statistics can be manipulated to suit one's own requirements.
5. Distrust of Statistics (рд╕рд╛рдВрдЦреНрдпрд┐рдХреА рдореЗрдВ рдЕрд╡рд┐рд╢реНрд╡рд╛рд╕)
"Statistics are like clay of which you can make a god or a devil as you please." Statistics do not prove anything by themselves; they can be misinterpreted or misused if not handled by experts.
Quick Tip for MP Board Exams (рдкрд░реАрдХреНрд╖рд╛ рдХреЗ рд▓рд┐рдП рдорд╣рддреНрд╡рдкреВрд░реНрдг рдЯрд┐рдкреНрд╕)
- Prepare the difference between Statistics in Singular Sense and Plural Sense clearly.
- Memorize the 5 stages of statistical methods in chronological order.
- Be ready with at least 4 characteristics of statistics in the plural sense.