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- 1. 1.A branch of mathematics dealing with the collection, analysis, interpretation and presentation of masses of numerical data. 2.A collection of quantitative data Definition
- 2. Scope of statistics 1. Statistics and planning: Statistics in indispensable into planning in the modern age which is termed as “the age of planning”. Almost all over the world the govt. are re- storing to planning for economic development. 2. Statistics and economics: Statistical data and techniques of statistical analysis have to immensely useful involving economical problem. Such as wages, price, time series analysis, demand analysis. 3. Statistics and business: Statistics is an irresponsible tool of production control. Business executive are relying more and more on statistical techniques for studying the much and desire of the valued customers.
- 3. 4. Statistics and industry: In industry statistics is widely used inequality control. In production engineering to find out whether the product is confirming to the specifications or not. Statistical tools, such as inspection plan, control chart etc. 5. Statistics and mathematics: Statistics are intimately related recent advancements in statistical technique are the outcome of wide applications of mathematics. 6. Statistics and modern science: In medical science the statistical tools for collection, presentation and analysis of observed facts relating to causes and incidence of dieses and the result of application various drugs and medicine are of great importance.
- 4. 7. Statistics, psychology and education: In education and physiology statistics has found wide application such as, determining or to determine the reliability and validity to a test, factor analysis etc. 8. Statistics and war: In war the theory of decision function can be a great assistance to the military and personal to plan “maximum destruction with minimum effort.” 9. In banking: it play an important role in banking. The banks make use of statistics for a number of purposes. The banks work on the principle that all the people who deposit their money with the banks do not withdraw it at the same time. The bankers use statistical approaches based on probability to estimate the numbers of depositors and their claims for a certain day.
- 5. 10. In State Management (Administration):Statistics is essential for a country. Different policies of the government are based on statistics. Statistical data are now widely used in taking all administrative decisions. it helps in estimating the expected expenditures and revenue from different sources. So statistics are the eyes of administration of the state. 11. In Accounting and Auditing: accounting is impossible without exactness. The correction of the values of current asserts is made on the basis of the purchasing power of money or the current value of it. In auditing sampling techniques are commonly used. An auditor determines the sample size of the book to be audited on the basis of error.
- 6. 12. In Natural and Social Sciences: it plays a vital role in almost all the natural and social sciences. Statistical methods are commonly used for analyzing the experiments results, testing their significance in Biology, Physics, Chemistry, Mathematics, Meteorology, Research chambers of commerce, Sociology, Business, Public Administration, Communication and Information Technology etc… 13. In Astronomy: Astronomy is one of the oldest branches of statistical study; it deals with the measurement of distance, sizes, masses and densities of heavenly bodies by means of observations. During these measurements errors are unavoidable so most probable measurements are founded by using statistical methods.
- 7. 15.Statistics and Government: The functions of a government are more varied and complex. Various depts. in the state are required to collect and record statistical data in a systematic manner for an effective administration. Data pertaining to various fields namely population, natural resources, production both agricultural and industrial, finance, trade, exports and imports etc are the most fundamental requirements of the state for its administration. 14. Statistics and Sociology: Sociology is one of the social sciences aiming to discover the basic structure of human society, to identify the main forces that hold groups together . It highlights and illuminates aspects of social life that otherwise might be only obscurely recognized and understood. The sociologist may be called upon for help with a special problem such as social conflict, urban plight or the war on poverty or crimes.
- 8. Functions of statistics 1.To Present Facts in Definite Form: we can represent the things in their true form with the help of figures. Without a statistical study, our ideas would be vague and indefinite. The facts are to be given in a definite form. If the results are given in numbers, then they are more convincing than if the results are expressed on the basis of quality. 2. Precision to the Facts: The statistics are presented in a definite form so they also help in condensing the data into important figures. So statistical methods present meaningful information. In other words statistics helps in simplifying complex data to simple-to make them understandable.
- 9. 3. Formulation and Testing of Hypothesis: These statistical methods help us in formulating and testing the hypothesis or a new theory. With the help of statistical techniques, we can know the effect of imposing tax on the exports of tea on the consumption of tea in other countries. The other example could be to study whether credit squeeze is effective in checking inflation or not. 4. Forecasting: Statistics is not only concerned with the above functions, but it also predicts the future course of action of the phenomena. We can make future policies on the basis of estimates made with the help of Statistics. We can predict the demand for goods in 2005 if we know the population in 2004 on the basis of growth rate of population in past. The statistics help in shaping future policies.
- 10. 5. Policy Making: With help of statistics we can frame favourable policies. How much food is required to be imported in 2007? It depends on the food-production in 2007 and the demand for food in 2007. Without knowing these factors we cannot estimate the amount of imports. On the basis of forecast the government forms the policies about food grains, housing etc. But if the forecasting is not correct, then the whole set up will be affected. 6. It Enlarges Knowledge: Whipple rightly remarks that “Statistics enables one to enlarge his horizon”. So when a person goes through various procedures of statistics, it widens his knowledge pattern. It also widens his thinking and reasoning power. It also helps him to reach to a rational conclusion. 8.
- 11. 7.To Measure Uuncertainty: Future is uncertain, but statistics help the various authorities in all the phenomenon of the world to make correct estimation by taking and analyzing the various data of the part. So the uncertainty could be decreased. As we have to make a forecast we have also to create trend behaviors of the past, for which we use techniques like regression, interpolation and time series analysis. 8. Reduces the Complexity of data: Statistics simplifies the complexity of data. The raw data are unintelligible. We make them simple and intelligible by using different statistical measures. Some such commonly used measures are graphs, averages, dispersions, skew ness, kurtosis, correlation and regression etc. These measures help in interpretation and drawing inferences. Therefore, statistics enables to enlarge the horizon of one's knowledge.
- 12. 9. Derives valid inferences : Statistical methods mainly aim at deriving inferences from an enquiry. Statistical techniques are often used by scholars planners and scientists to evaluate different projects. These techniques are also used to draw inferences regarding population parameters on the basis of sample information. 10. Simplification of Complex Facts: The foremost purpose of the statistics is to simplify huge collection of numerical data. It is beyond the reach of human mind to remember and recollect the huge facts and figures. Statistical method makes it possible to understand the whole in the short span of time and in a better way.
- 13. 11. Relationship between Facts: Statistical methods are used to investigate the cause and effect relationship between two or more facts. The relationship between demand and supply, money-supply and price level can be best understood with the help of statistical methods. 12. Relationship between Facts: Statistical methods are used to investigate the cause and effect relationship between two or more facts. The relationship between demand and supply, money-supply and price level can be best understood with the help of statistical methods. 13. To Indicate Trend Behaviour: Statistics helps to indicate trend behaviour certain fields of enquiry. The statistical techniques like Analysis of Time Series Extrapolation etc. are highly used to know the trend behaviour of the enquiry in question.
- 14. 14. Classification of Data: Classification refers to a process of splitting up the data into certain parts which helps in the matters of comparison and interpretation of the various features of the data. This is done by the various improved techniques statistics. 15.To Draw Rational Conclusion: In various fields of uncertainty like business and commerce, it is very much necessary to draw rational conclusions on the basis of facts collected and analyzed. For this, the mind of the decision maker should be free from any bias and prejudices.
- 15. Characteristics of statistics 1.Statistics should be numerically expressed. For example the statement rajan is of height 6' 1" makes the fact clear and easily understandable. 2. Statistics are aggregates of facts. Statistics means the facts pertaining to a group of individuals or individual item. 3. Statistics are affected to a market extent by a multiplicity of causes. There are a variety of forces or factors operating on the facts and figures in an aggregate. The influence of any particular factor cannot be isolated.
- 16. 7.It should be collected for a pre-determined purpose . Any data collected without a pre-determined purpose may not be appropriate and useful for a purpose decided later on the vehicles passing by him, it will not amount to statistics for that there is no purpose behind the collection of such data. 4. Statistics must be collected in a systematic manner for a predetermined purpose. Determination of the main purpose or objectives of any scientific study is the first and the most important step which in turn paves way for other operations to follow. 5. Statistics are enumerated or estimated according to reasonable standards of accuracy. 6. Statistics should be placed in relation to each other.
- 17. Advantages of statistics • They are familiar to library staff and managers • They can be analyzed relatively quickly • Information is collected in a standardized way • They are usually straightforward to analyze • They overcome the difficulties of encouraging participation by users
- 18. • They are often required and respected by decision-makers within the institution and beyond eg funders, government • They support qualitative data obtained from questionnaires, interviews etc with 'hard facts' • They are useful for benchmarking purposes. •Systematic samples are relatively easy to construct, execute, compare and understand. This is particularly important for studies or surveys that operate with tight budget constraints. •A systematic method also provides researchers and statisticians with a degree of control and sense of process.
- 19. •Clustered selection, a phenomenon where randomly chosen samples are uncommonly close together in a population, is eliminated in systematic sampling. •Perhaps the greatest strength of a systematic approach is its low risk factor. The primary potential disadvantages of the system carry a distinctly low probability of contaminating the data. • Statistics is used to determine validity, reliability, and significance depending on what is used for in the market. • It can be used to collect wide range of information- attitudes, values, beliefs, past behaviors etc •There is a wealth of information because of standardized collection of data through statistical survey performed by the government, corporations, businesses, individuals etc.
- 20. Disadvantages of statistics • They are not an appropriate method to understand issues in great depth and identify ways to solve problems highlighted • they are not suitable to evaluate user opinions, needs or satisfaction with services • It may be time-consuming to arrange methods of data collection eg contacting vendors, liaising with IT departments
- 21. •The systematic method assumes that the size of the population is available or can be reasonably approximated. •A population needs to exhibit a natural degree of randomness along the chosen metric. If the population has a type of standardized pattern, the risk of accidentally choosing very common cases is more apparent. •There is a greater risk of data manipulation with systematic sampling because researchers might be able to construct their systems to increase the likelihood of achieving a targeted outcome rather than letting the random data produce a representative answer. Any resulting statistics could not be trusted.
- 22. Limitations of statistics The statistical methods don’t study the nature of phenomenon which cannot be expressed in quantitative terms. When even phenomena happen, that is due to many causes, but all these causes can not be expressed in terms of data. So we cannot reach at the correct conclusion. It is liable to be miscued. So we can say that we can check the data and procedures of its approaching to conclusions. As it is a delicate science and can be easily misused by an unscrupulous person.
- 23. •In this subject we use so many methods to find a single result. Variation can be found by quartile deviation, mean deviation or standard deviations and results vary in each case. • Statistical results are not always beyond doubt because they are unable to give complete solution to a problem, the result must be taken and used with much wisdom. •Statistics does not deal with isolated measurement •Statistics deals with only quantitative characteristics •Statistics laws are true on average. Statistics are aggregates of facts. So single observation is not a statistics, it deals with groups and aggregates only.
- 24. •Statistical methods are best applicable on quantitative data. •Statistical cannot be applied to heterogeneous data. •It sufficient care is not exercised in collecting, analyzing and interpretation the data, statistical results might be misleading. •Only a person who has an expert knowledge of statistics can handle statistical data efficiently. •Some errors are possible in statistical decisions. Particularly the inferential statistics involves certain errors. We do not know whether an error has been committed or not.