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About Statistics Assignment: The statistics assignment help of the online statistics tutors can be availed by the students on our website very conveniently. Most of the services of online tutors in statistics nowadays are no longer free. Statistics means the practice or science of collecting and analysing numerical data in large quantities, especially for the purpose of inferring proportions in a whole from those in a representative sample. But the prices we offer are very affordable and the students will surely like the benefits of their helpful guides and solutions while having a tutorial lesson in Statistics for their assignments. All our statistics experts are capable of handling different kinds of Statistics Help Online that are present in the course curriculum of university and colleges in the present time. Statistics assignment Sample Questions and Answers:
Question 1 : Define Rank Correlation and derive p (X. Y). Ans. Let us suppose that a group of n individuals is arranged in order of merit or proficiency in possession of two characteristics A and B. These ranks in the two characteristics will, in general, be different B. These ranks in the two characteristics will, in general. be different For example, if we consider the relation between intelligence and beauty. it is not necessary that a beautiful individual is intelligent also. Let (x, y) : I = 1, 2‌. n be the rank of the ith individual in two characteristics A and B respectively. Pearsonian coefficient of correlation between the ranks x’, s and �� ’ is called the rank correlation coefficient between A and B for that group of individuals. Derivation of p(X, Y) : We have P(X,Y) = [
x− x Y− Y (x− x)2 . (Y− Y)2
đ?‘Ľđ?‘Ś
=
đ?‘Ľ 2. đ?‘Ś 2
‌(1)
Where x = X - đ?‘Ľ . y = Y - đ?‘Œ. If X and Y each takes the values 1,2,‌.. n then đ?‘Ľ = 2 = đ?‘Ś
and nđ?œŽ
2 = đ?‘Ľ
Also
đ?‘‘ 2 = (đ?‘Ľ − đ?‘Ś)2 = (đ?‘Ľ − đ?‘Ľ) – (Y - đ?‘Œ)]2 =
đ?‘Ľ2 =
=
đ?‘‘2 =
đ?‘Ľ2 +
=
đ?‘Ľđ?‘Ś = ( đ?‘Ľ 2 +
1 2
đ?‘› (đ?‘› 2 −1) 12
and nđ?œŽ
đ?‘Ś2 =
đ?‘›+1 2
=đ?‘Œ
đ?‘› (đ?‘› 2 −1)
‌(2)
12
đ?‘Ľâˆ’đ?‘Ś
2
đ?‘Ś 2 - 2 đ?‘Ľđ?‘Ś đ?‘Ś2 -
2
đ?‘‘ )
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We shall now investigate the effect of common ranking (in case of ties). on the sum of squares of the ranks. Let � 2 and S12 denote that sum of the squares of united and lied ranks respectively. Then we have:
Question 2 : Report the data given in the illustration 13 by a frequency polygon drawn straightway. Solution Frequency Polygon (Showing the wage distribution of a group of workers)
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Question 3 : The equation for yearly sales (in ’000 $.) for a commodity with the year, 2003 as origin is Yc =91.6 + 28.8X. Determine the trend equation to give the monthly trend values with Jan ’04. Since, the conversion is required to be made from a higher periodical base (annual) to a lower periodical base (monthly), it is necessary to attempt on the conversion first, and then on shifting of the trend origin as follows : (ii) Conversion of the trend By the formula of conversion of an annual trend into a monthly one we have, �
đ?‘?đ?‘‹
Yc = 12 + 12 Ă—12 Substituting the respective values, in the above we get, Yc =
91 .6 12
28.8đ?‘‹
+ 12 Ă—12 = 7.63 + 0.2X
Thus, Yc = 7.63 + 0.2 Y When X unit = 1 month, and Y unit = monthly sales (ii) Shifting of the Trend Origin Here, it is required to shift forward the trend origin by 6.5 months i.e. from 1st July, 03 (the midpoint of the year, 03) to the 15th Jan, 04 (the midpoint of the month). Thus, K = 5.5 Copyright Š 2012-2016 Economicshelpdesk.com, All rights reserved
By the formula of shifting a trend we have, Yc = a + b (X + K) Substitution the respective values in the above we get, Yc = 7.63 + 0.2 (X + 6.5) = 7.63 + 0.2X + 1.3 = 8.93 + 0.2 Y Yc = 8.93 + 0.2 X Where, the point of origin is Jan ’03, X unit = 1 month, and Y unit monthly sales. (iii) Calculation of the trend value for March ’04 The time deviation of March ’04 from the trend origin Jan ’04, or X = 2 Thus, when X = 2, Yc = 8.93 + 0.2 (2) = 8.93 + 0.4 = 9.33 Hence, the trend value for March ’04 will be 9.33.
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