MBA 1st Year Business Statistics Unit 1 Very Short Question Answer Notes Study Material Unit wise Chapter Wise Notes Syllabus Scope, function and limitations of statistics, Measures of Central Tendency-Mean, Median, Mode, Percentiles, Quartiles, Measures of Dispersion-Range, Interquartile range, Mean Deviation, Mean absolute deviation, Standard Deviation, Variance, Coefficient of Variation. Measures of Shape and Relative location; Skewness and Kurtosis; Chebyshev’s Theorem. Topic Wise Syllabus Of The Content Study Notes.
Very Short Questions Answers
.1 . Define the term statistics.
Ans. By statistics, we mean aggregates of facts affected to a marked extent by multiplicity of causes numerically expressed or estimated according to reasonable standards of accuracy, collected in a systematic manner for a predetermined purpose and placed in; relatikon to each other.
Q.2. Give any four characteristics of good average.
Ans. The characteristics of good average are:
- It should be based on all the items.
- It should be easy to understand and simple to calculate.
- It should not be affected much by extreme values.
- It should be rigidly defined so that conclusion remains uniform irrespective of enumeration by any person.
Q.3. what do you understand by arithmetic mean?
Ans. Arithmetic mean or arithmetic average, which is popularly known as mean, is obtained by dividing the sum of all the values by the number of items.
‘Arithmetic mean is the amount secured by dividing the sum of values of the items in a series by their number.’
Q.4. Write the meaning of weighted arithmetic mean.
Ans. In this type of mean, each observation is assigned weight according to its importance. For its calculation each observation is multiplied by its respective weight and the sum of such products its divided by the sum of the weights.
Q.5. Write the meaning of mid value of arithmetic mean.
Ans. Sometimes it may be possible that mid values are given in place of class intervals. In such situations class intervals are not necessary for calculating arith3metic mean. But mean can directly be obtained.
Q.6. Define the case of inclusive series in arithmetic mean.
Ans. If the data is given in the form of an inclusive series, there is no need to change it into an exclusive series because mid – point of the class remains unaffected in this case. Rest of the procedure is the same.
Q.7. Write the meaning of Charlier’s accuracy check.
Ans. With the help of this check, accuracy of calculation incolved in the computation of mean 4can be checked. This check is applicable equally to discrete as well as continuous frequency distribution. The formula given by Charlier is as under:
Ef7 (d’ + 1) = E fd’ + Ef
If left hand side is equal to right hand side, we say that calculations are correct. For checking the accuracy of calculation, and additional column is formed. This column is F (d’ + 1).
Q.8. the sum of squars of the deviations from arithmetic mean is minimum. Show how.
Ans. Sum of square of the deviations about mean is less as compared to sum of the squares of the deviations about any arbitraty value A.
Symbolically, E (X – X)2 < E (X – A)2
Q.9. Define the meaning of combined arithmetic mean with formula.
Ans. A combined mean can be obtained if two or more means with their number observations are given, The combined mean for two group having N1 and N2 observations respectively, is given by
Q.10. Define median.
Ans. Median is the central value average. It may be defined as the middle number of the series. It is obtained by observing the middle point value of the data. This type of average is called positi23onal average. Partition value and mode are also positional averages.
Q.11. Wha is meant by mode?
Ans. The word “Mode’ has its origin fro1m French word ‘La-mode’ which means fashion or the most popular phenomenon. In this context, it is sais that ‘Mode means most fashionable item.’
Q.12. Write the equation of empirical mode.
Ans. Mode may also be calculated on the basis of its relationship with mean and median by applying the following equatikons:
Mode = 3 Median -2 Mean or X = 3M -2X
Such mode is called as ‘Empirical mode’.
Q.13. Write the formula for determination of modal value of mode
Ans. Formula for determination of modal value of mode
Q.14. Define the two merits and demerits of mode.
Ans. Merits of mode: These are as follows:
- Not affected by extreme values.
Demerits of mode: 1. Indeterminate and ill – defined.
- Not based on all values.
Q.15. Define the term geometric mean.
Ans. Geometric mean is the nth root of the product of n values of a series. It means, if there are two values, we take square root of the product of these two values, i.e. geometric mean of a and b would be equal to similarily, the geometric mean of a, b and c will be equal to cube root of the product, i.e.
Q.16. What is weighted geometric mean?
Ans. If there is difference in relative importance of different values in a series, weighted geometric mean may be used. Weighted geometric mean is the nth root of the product of various values raised to the power of their respective weights.