This page contains short questions and answers about introductory statistics which includes history of statistics, Meaning of Statistics, Symbols and Notations, Data and Variable, Uses and Limitation of statistics. Question 1: What is meant by Statistics? Meaning of Statistics The word Statistics is from the Latin word status, meaning political state, and originally meant information useful to the state, but now this word is being used in different meanings.
Formal Definition of Statistics Statistics is a branch of mathematics which involves the collection, organization, interpretation, and presentation of data, To draw inference about the data collected from population under study Question 2: What are the Branches of Statistics? Branches of Statistics As a subject Statistics can be divided into Descriptive Statistics and Inferential Statistics.
Question 3: What are the Characteristics of Statistics? Some of the important characteristics of Statistics are:
Question 4: What are the uses of Statistics?
Question 5: What is uncertainty? Uncertainty refers to the incompleteness and the instability of data available. I does not imply ignorance. Decision in statistics are made on the basis of sample evidence, as sample cannot have absolutely certain information. Question 6: What is Statistic? A statistic is a quantity that is calculated from a sample data. It is used to provide information about unknown values in the corresponding population from which sample is drawn. For example, the average (mean value) of the data in a sample is used to give information about the overall average in the population from which that sample was taken. It is possible to draw more than one sample from the same population and in general, that's why the value of a statistic will vary from sample to sample. i.e. The average values in more than one sample, drawn from the same population, will not necessarily be equal. Statistics are often assigned Roman letters or English letters (e.g. $\overline{X}$,$\sigma^2$). Question 7: What is
Parameter? A parameter is a quantity that is calculated from population data. Parameters are denoted by Greek letters. For example Population mean is represented $\mu$ and Population Variance is represented by $\sigma^2$. Parameter is constant because it does not change from the same population. Question 8: What is population? A population is any entire collection of people, animals, plants or things from which we may collect data. It is the entire group we are
interested in, from which we wish to describe or draw conclusions about. In order to make any generalizations about a population, a sample, that is meant to be representative of the population, is often studied. For each population there are many possible samples. Question 9: What is a Sample? A
sample is a group of units selected from a larger group (called population), i.e. it is small part of population. To draw valid conclusions about the population under study, sample(s) is/are generally selected because usually the population is too large to study. The sample should be representative of the population. Samples are selected by using some sampling techniques. Also, before collecting the sample, it is important that the researcher carefully and completely defines the population,
including a description of the members to be included. Question 10: What is the difference between a Nominal and an Ordinal scale? Nominal ScaleThe classification or grouping of the observations into mutually exclusive qualitative categories or classes is said to constitute a nominal
scale. Ordinal Scale It includes the characteristic of a nominal scale and in addition has the property of ordering or ranking of measurements. For example, the performance of students (or players) is rated as excellent, good fair or poor, etc. Number 1, 2, 3, 4 etc. are also used to indicate ranks. The only relation that holds between any pair of categories is that of "greater than" (or more preferred) Question 11: What is descriptive and inferential/ Inductive Statistics.? In Descriptive Statistics we usually use the graphical and numerical techniques to organize, summarize and present the information contained in a data set in informative way. Its grounds are measure of central tendency and measure of dispersion. Question 12: Define the term Variable. A characteristic that differs either in quality or quantity from object to object, place to place, time to time is called variable. For example, beauty, intelligence, age, year, inflation, etc are example of variable. Question 13: Define the term Constant. A characteristic that does not change/ differ in quantity from object to object, place to place, time to time is called constant. For example, Total marks of a paper and number of days in a week. Question 14: Differentiate between Quantitative and Qualitative Variable.
Question 15: Which kind of data can increase or decrease continuously? Continuous data can increase or decrease continuously. Question 16: What is proper definition of DATA? DATA is collection of facts & figure for specific purpose, organized for analysis or used to reason or make decisions. Question 17: What is meant by "attribute"? Attributes: Qualitative characteristics of variable is also called attributes for example poverty, intelligence etc. are attributes. Question 18: Explain Primary and Secondary data. Primary data: Initially collected data in its first creative form is called primary data. It is also called raw data or ungrouped data. For example, data collected by NADRA to issue computerized identity cards. Secondary data are data that already exist in industry-specific reports, previous research on the topic of interest, or data from an organization's own database. Qualitative sources of secondary data include magazine and newspaper articles and annual reports of industry participants. However, secondary data can also provide a rich source of information. Or Primary data changed into any other form according to the requirement of the investigator is called secondary data. Secondary data is not collected but it is obtained by changing the form of primary data. Question 19: What is mean by grouped and Raw data? Grouped data: The data presented in the form of frequency distribution is also known as grouped data. Raw data: Data that have not been processed in any manner. It often refers to uncompressed text that is not stored in any priority format. It may also refer to recently captured data that may have been placed into a database structure, but not yet processed. Question 20: Name the sources of collecting Primary Data.
Question 21: What are the sources of Secondary Data?
Question 22: What is observation give details? Observation:In statistics, an observation often means any sort of numerical information recorded, it may be a physical measurement such as height, weight, age etc; a classification (grouping) such as heads or tails; or an answer to a question such as yes or no. Question 23: Name some department names where Statistics is applied?
What is the branch of statistics that deals with the presentation and collection of data?Descriptive statistics deals with the presentation and collection of data. This is usually the first part of a statistical analysis.
What are the branch of statistics?There are three real branches of statistics: data collection, descriptive statistics and inferential statistics.
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