ICS Part 2 Online Preparation for Statistics Short questions Chapter Wise

"Regression coefficients are independent of origin". What does it mean ?

• Ans 1: It means that addition or subtraction of a constant to the values of variables have no effect on the values of regression coefficients.

What are the demerits of moving average method ?

• Ans 1: It generates new cycles; fails to give a mathematical model for forecasting; some data are lost in the beginning and end.

What is random sampling ?

• Ans 1: it is the process of selecting a part or some elements from the population using probability theory.

• Ans 1: Option (ii) is true.

What do you know about DOS?

• Ans 1: A DOS, or disk operating system, isan operating system that runs from a disk drive. The term can also refer to a particular family of disk operating systems, most commonly MS-DOS, an acronym for Microsoft DOS.

Is it true that failure to reject the H₀ means the acceptance of H_A ?

• Ans 1:

• Ans 1:

Describe the difference between operating system and application software ?

• Ans 1: An operating system is an integrated set of specialized programs that is used to control and manage the resources and overall operations of a computer, like input/ output control, storage management etc.While application software are computer programs, which are developed for user related tasks and to serve the specific needs. For example, the programs for payroll processing, video games, word processor etc, belong to this category.

What are the basic components of time series ?

• Ans 1: i. Secular Trend.
  ii. Cyclical Variation.
  iii. Seasonal Variation.
  iv. Irregular Variation.

What is meant by sampling with replacement ?

• Ans 1: A scheme in which elements can be selected more than once.

What is mean by "Level of Confidence" ?

• Ans 1: It is the confidence coefficient expressed in percentage form.

What is statistic ?

• Ans 1: It is the numerical descriptive of sample.

What is the meant by proportion ?

• Ans 1: It is the ratio of number of elements possessing a given characteristic in the population or sample to the total number of elements in the population or sample.

What is meant by a Noise ?

• Ans 1: The irregular component of a time series is known as "Noise".

What is meant by central limit theorem ?

• Ans 1: This theorem states that if we increase the sample size sufficiently then distribution of sample estimator approaches normality even if the parent population of the sample was not normal.

• Ans 1: Approximately 68.26% and 99.73% of the total area fall in the stated intervals respectively.

What is meant by standard error of a statistic ?

• Ans 1:

Is it true that a change in origin scale of the variables affects the value of correlation coefficient ?

• Ans 1: Coefficient of correlation is independent of the change in the origin and scale.

• Ans 1:

Define type of computer.

Digital computer

Analogue computer

Hybrid computers

• Ans 1: Digital Computer: Digigal computer proces data in numerical form using digigal circuits.They perfom arithemetic and logic operations with discrete values. These values are 0 and 1.
• Ans 2: Analogue Computer: The analog computers accept input and give output in the form of analog singals. The output is measured on a scale.These computers use electronic and mechanical phenomena to solve a problem by convering one kind of physical quantity into another the analogue computer have very high speed computing elements used to process physical quantities.
• Ans 3: Hybrid Computer: Hybrid computers are teh combination of analoue and digital computers. These computers contain both digital and analouge components. In Hybrid computers, the users can process data. These are special purpose computer. These computers are used in robotices and medical labs.