Quiznetik

Business Statistics | Set 1

1. The sum of deviations of observations from their arithmetic mean:

Correct : C. Zero

2. The sum of absolute deviations is minimum when taken from:

Correct : B. Median

3. The sum of squared deviations is minimum when taken from:

Correct : A. Mean

4. What is the median of 33, 86, 68, 32, 80, 48, 70?

Correct : B. 68

5. In a moderately skewed distribution, the value of mean is 16 and that of mode is 25.

Correct : B. 19

6. In a moderately skewed distribution, the following equation indicates the relationship among mean, median and mode:

Correct : B. Mode = 3 Median – 2 Mean

7. For a symmetrical distribution, Q1 and Q3 are 20 and 60 respectively. The value of median will be:

Correct : C. 40

8. The variate values which divide a series into ten equal parts are called:

Correct : B. Deciles

9. From which average, the sum of deviations is zero?

Correct : A. Mean

10. The average to be used to determine the average size of the shoe sold in a shop is:

Correct : C. Mode

11. Find the Mode of 5, 3, 27, 5, 9, 3, 8, 5:

Correct : A. 5

12. In a moderately asymmetrical distribution, the value of mean is 75 and the value of mode is 60:

Correct : B. 70

13. Given Mean = 70.2 and mode = 70.5. Find the median using empirical relationship among them.

Correct : B. 150

14. In a moderately skewed distribution, the value of mode is 120 and that of median is 140. Find the value of arithmetic mean.

Correct : A. 150

15. The arithmetic mean of the marks obtained by 50 students was calculated as 44. It was later discovered that a score of 36 was misread as 56. Find the correct value of arithmetic mean of the marks obtained by the students.

Correct : B. 43.6

16. The marks obtained by 9 students in a test are 25, 20, 15, 45, 18, 7, 10, 38 and 12. Find the median.

Correct : C. 18

17. In a moderately asymmetrical distribution, the mode and mean are 32.1 and 35.4 respectively. Calculate the median.

Correct : B. 34.3

18. In a moderately skewed distribution, the mode and median are 20 and 24 respectively. Calculate the value of mean.

Correct : B. 26

19. The mean weight of 150 students in a class is 60 Kg. The mean weight of Boy students is 70 Kg and that of a girl students is 55 kg. Find the number of Boys and Girls in the class.

Correct : A. 50 and 100

20. A distribution consists of three components with total frequencies of 200, 250 and 300 having means 25, 10 and 15 respectively. Find the mean of the combined distribution.

Correct : B. 16

21. The arithmetic mean is 12 and the number of observations are 20 then the sum of all the values is

Correct : C. 240

22. The method used to compute average or central value of the collected data is considered as

Correct : B. measures of central tendency

23. The mean or average used to measure central tendency is called

Correct : B. arithmetic mean

24. If the mean of percentages, rates and ratios is to be calculated then the central tendency measure which must be used in this situation is

Correct : A. weighted arithmetic mean

25. In the quartiles, the central tendency median to be measured must lie in

Correct : B. second quartile

26. A numerical value used as a summary measure for a sample, such as sample mean, is known as a

Correct : C. sample statistic

27. The mean of a sample is

Correct : D. computed by summing all the data values and dividing the sum by the number of items

28. In a five number summary, which of the following is not used for data summarization?

Correct : D. the 25th percentile

29. Since the mode is the most frequently occurring data value, it

Correct : C. is always larger than the mean

30. In statistics out of 100, marks of 21 students in final exams are as 90, 95, 95, 94, 90, 85, 84, 83, 85, 81, 92, 93, 82, 78, 79, 81, 80, 82, 85, 76, 85 then mode of data is

Correct : A. 85

31. Branches of statistics includes

Correct : D. both a and b

32. What is the median of the data 78, 56, 22, 34, 45, 54, 39, 68, 54, 84?

Correct : A. 54

33. Find the mean of x + 77, x + 7, x + 5, x + 3 and x – 2?

Correct : B. x + 18

34. In the class intervals 40 – 50, 50 – 60, the number 50 is included in which of the following?

Correct : C. 50 – 60

35. If each observation of the data is increased by 5, then what happens to its mean?

Correct : B. is increased by 5

36. The measurements of spread or scatter of the individual values around the central point is called:

Correct : A. Measures of dispersion

37. The scatter in a series of values about the average is called:

Correct : B. Dispersion

38. The measures used to calculate the variation present among the observations in the unit of the variable is called:

Correct : C. Absolute measures of dispersion

39. The measures used to calculate the variation present among the observations relative to their average is called:

Correct : D. Relative measures of dispersion

40. The degree to which numerical data tend to spread about an average value called:

Correct : C. Variation

41. The measures of dispersion can never be:

Correct : C. Negative

42. If all the scores on examination cluster around the mean, the dispersion is said to be:

Correct : A. Small

43. If there are many extreme scores on all examination, the dispersion is:

Correct : A. Large

44. Given below the four sets of observations. Which set has the minimum variation?

Correct : D. 48, 49, 50, 51, 52

45. Which of the following is an absolute measure of dispersion?

Correct : C. Standard deviation

46. The measure of dispersion which uses only two observations is called:

Correct : C. Range

47. The measure of dispersion which uses only two observations is called:

Correct : A. Range

48. In quality control of manufactured items, the most common measure of dispersion is:

Correct : A. Range

49. The range of the scores 29, 3, 143, 27, 99 is:

Correct : A. 140

50. If the observations of a variable X are, -4, -20, -30, -44 and -36, then the value of the range will be:

Correct : B. 40

51. The range of the values -5, -8, -10, 0, 6, 10 is:

Correct : D. 20

52. If the maximum value in a series is 25 and its range is 15, the maximum value of the series is:

Correct : A. 10

53. Half of the difference between upper and lower quartiles is called:

Correct : B. Quartile deviation

54. If Q3=20 and Q1=10, the coefficient of quartile deviation is:

Correct : B. 1/3

55. If the quartile range is 24 then the quartile deviation is:

Correct : B. 12

56. The sum of all the squared deviations is divided by the total number of observations to calculate

Correct : B. population variance

57. For the recorded observation, the ratios measured by absolute variation are considered as

Correct : B. relative measures

58. If the arithmetic mean is multiplied to coefficient of variation then the resulting value is classified as

Correct : B. coefficient of mean

59. If mean absolute deviation of set of observations is 8.5 then value of quartile deviation is

Correct : A. 7.08

60. For a positively skewed distribution, mean is always:

Correct : C. Greater than the mode

61. If the sum of deviations from median is not zero, then a distribution will be:

Correct : B. Skewed

62. The degree of peaked ness or flatness of a unimodel distribution is called:

Correct : D. Kurtosis

63. In a mesokurtic or normal distribution, µ4 = 243. The standard deviation is:

Correct : D. 3

64. In a symmetrical distribution, Q3 – Q1 = 20, median = 15. Q3 is equal to:

Correct : D. 25

65. The first three moments of a distribution about the mean are 1, 4 and 0. The distribution is:

Correct : A. Symmetrical

66. For a symmetrical distribution:

Correct : C. β1 = 0

67. The second and fourth moments about mean are 4 and 48 respectively, then the distribution is:

Correct : C. Mesokurtic or normal

68. Bowley's coefficient of skewness lies between:

Correct : B. 1 and +1

69. The value of β2 can be:

Correct : D. All of the above

70. If the sum of squares of the rank differences of 10 pairs of values is 30, find the correlation coefficient between them.

Correct : B. 0.82

71. In a bivariate sample, the sum of squares of differences between marks of observed values of two variables is 33 and the rank correlation between them is 0.8. Find the number of pairs of observations:

Correct : B. 10

72. In a bivariate distribution, Spearman’s Coefficient of Correlation is -0.25. If the sum of the squares of various ranks is 150, find out the number of pairs of items:

Correct : C. 9

73. The rank correlation coefficient of a debating contest involving 10 participants was calculated as 0.6. However, it was later discovered that the difference in the ranks of some participants was read as 8 instead of 3. Find the correct correlation coefficient:

Correct : A. 0.933

74. The regression coefficient of X on Y is:

Correct : A. bXY

75. Regression Coefficient of Y on X is:

Correct : B. bYX

76. If one of the regression coefficient is greater than unity, the other must be:

Correct : B. Less than Unity

77. The regression coefficients re independent of change of origin but:

Correct : A. Not of Scale

78. The coefficient of correlation between the regression coefficients is:

Correct : B. Geometric Mean

79. The correlation coefficient is used to determine:

Correct : C. The strength of the relationship between the x and y variables

80. If there is a very strong correlation between two variables then the correlation coefficient must be:

Correct : B. much smaller than 0, if the correlation is negative

81. In regression, the equation that describes how the response variable (y) is related to the explanatory variable (x) is:

Correct : B. the regression model

82. In regression analysis, the variable that is being predicted is the:

Correct : A. Response, or dependent, variable

83. In a regression analysis if r2 = 1, then :

Correct : B. SSE must be equal to zero

84. In regression analysis, the variable that is used to explain the change in the outcome of an experiment, or some natural process, is called:

Correct : C. the predictor variable

85. If the coefficient of determination is a positive value, then the regression equation:

Correct : C. could have either a positive or a negative slope

86. If two variables, x and y, have a very strong linear relationship, then:

Correct : A. there is evidence that x causes a change in y

87. If the coefficient of determination is equal to 1, then the correlation coefficient :

Correct : B. can be either -1 or +1.

88. In regression analysis, if the independent variable is measured in kilograms, the dependent variable:

Correct : D. can be any units

89. The strength (degree) of the correlation between a set of independent variables X and a dependent variable Y is measured by

Correct : A. Coefficient of Correlation

90. The percent of total variation of the dependent variable Y explained by the set of independent variables X is measured by:

Correct : C. Coefficient of Determination

91. A coefficient of correlation is computed to be -0.95 means that:

Correct : C. The relationship between two variables is strong and but negative

92. Let the coefficient of determination computed to be 0.39 in a problem involving one independent variable and one dependent variable. This result means that:

Correct : C. 39% of the total variation is explained by the independent variable

93. Relationship between correlation coefficient and coefficient of determination is that:

Correct : B. The coefficient of determination is the coefficient of correlation squared

94. The value of a correlation is reported by a researcher to be r = −0.5. Which of the following statements is correct?

Correct : A. The x-variable explains 25% of the variability in the y-variable.

95. Past data has shown that the regression line relating the final exam score and the midterm exam score for students who take statistics from a certain professor is: final exam = 50 + 0.5 × midterm One interpretation of the slope is

Correct : A. a student who scored 0 on the midterm would be predicted to score 50 on the final exam.

96. One use of a regression line is

Correct : D. to estimate the change in y for a one-unit change in x.

97. The percent of total variation of the dependent variable Y explained by the set of independent variables X is measured by

Correct : C. Coefficient of Determination

98. The strength (degree) of the correlation between a set of independent variables X and a dependent variable Y is measured by

Correct : D. All of the above

99. A coefficient of correlation is computed to be -0.95 means that

Correct : C. The relationship between two variables is strong and but negative

100. Relationship between correlation coefficient and coefficient of determination is that

Correct : B. The coefficient of determination is the coefficient of correlation squared