Which of the following statements are true? 1. The coefficient of rank correlation has the same limits as the Karl Pearson's coefficient of correlation. 2. The coefficient of correlation is independent of the change of origin but not of scale. 3. The covariance between $$X$$ and $$Y$$ is defined as $$\frac{{\sum {xy} }}{n}$$ where, $$x = \left( {X - \overline X } \right),y = \left( {Y - \overline Y } \right)$$ and $$n = $$ no. of paired observations. 4. $${b_{xy}}$$ is called regression coefficient of $$X$$ variable on $$Y$$ variable. 5. If $${b_{xy}}$$ is 0.4 and $${b_{yx}}$$ is 1.6, coefficient of determination would be 0.8. Select the correct answer:

The following Boolean expression $$Y = A \cdot \overline B \cdot \overline C \cdot \overline D + \overline A \cdot B \cdot \overline C \cdot D + \overline A \cdot \overline B \cdot \overline C \cdot D + \overline A \cdot \overline B \cdot \overline C \cdot D + \overline A \cdot B \cdot C \cdot D + A \cdot \overline B \cdot \overline C \cdot D$$ can be simplified to

A

$$\overline A \cdot \overline B \cdot C + A \cdot \overline D $$

B

$$\overline A \cdot B \cdot \overline C + A \cdot \overline D $$

C

$$A \cdot \overline B \cdot \overline C + \overline A \cdot D$$

D

$$A \cdot \overline B \cdot C + \overline A \cdot D$$

Which of the following statements relating to correlation and reegression are true?
1. The coefficient of correlation is independent of change of origin and scale
2. The coefficient of correlation between the two variables is the arithmetic average of the two regression coefficients
3. The probable error of the coefficient correlation is 0.6745 times of its standard error
4. Coefficient of correlation multiplied by the ratio between the standard deviations of the two variables denotes the slope of the regression line
Select the correct answer:

A

1, 2 and 3

B

1, 3 and 4

C

Both 2 and 4

D

2, 3 and 4

Statement I The product of coefficient of correlation, standard deviation of variable 'X' and Standard deviation of variable 'Y' gives the measure of covariance between X and Y variables.
Statement II The product of coefficient of correlation between X and Y variables and the ratio between standard deviation of X variable to standard deviation of Y variable measures the slope of the regression line of X on Y variable.

A

Both statements are correct

B

Both statements are incorrect

C

Statement I is correct while Statement II is incorrect

D

Statement I is incorrect while Statement II is correct

If a + b + c + d = 4, then find the value of $$\frac{1}{{\left( {1 - a} \right)\left( {1 - b} \right)\left( {1 - c} \right)}}$$ + $$\frac{1}{{\left( {1 - b} \right)\left( {1 - c} \right)\left( {1 - d} \right)}}$$ + $$\frac{1}{{\left( {1 - c} \right)\left( {1 - d} \right)\left( {1 - a} \right)}}$$ + $$\frac{1}{{\left( {1 - d} \right)\left( {1 - a} \right)\left( {1 - b} \right)}}$$ is?

A

0

B

5

C

1

D

4

If a + b + c + d = 4, then the value of $$\frac{1}{{\left( {1 - a} \right)\left( {1 - b} \right)\left( {1 - c} \right)}}$$ + $$\frac{1}{{\left( {1 - b} \right)\left( {1 - c} \right)\left( {1 - d} \right)}}$$ + $$\frac{1}{{\left( {1 - c} \right)\left( {1 - d} \right)\left( {1 - a} \right)}}$$ + $$\frac{1}{{\left( {1 - d} \right)\left( {1 - a} \right)\left( {1 - b} \right)}}$$ is?

A

0

B

1

C

4

D

1 + abcd

The quark content of $$\sum {^ + } ,\,{K^ - },\,{\pi ^ - }$$ and p is indicated: $$\left| {\sum {^ + } } \right\rangle = \left| {uus} \right\rangle ;\,\left| {{K^ + }} \right\rangle = \left| {s\overline u } \right\rangle ;\,\left| \pi \right\rangle = \left| d \right\rangle ;\,\left| p \right\rangle = \left| {uud} \right\rangle $$
In the process, $${\pi ^ - } + p \to {K^ - } + \sum {^ + } ,$$ considering strong interactions only, which of the following statements is true?

A

The process is allowed because ΔS = 0

B

The process is allowed because $$\Delta {I_3} = 0$$

C

The process is not allowed because ΔS ≠ 1 and $$\Delta {I_3} \ne 0$$

D

The process is not allowed because the Baryon number is violated

Let the average temperatures in Centigrade (C) and Fahrenheit (F) be $$\overline C $$ and $$\overline F $$. If $$\overline C $$ and $$\overline F $$ are related to $$F = \frac{9}{2}C + 32,$$ then $$\overline F $$ and $$\overline C $$ have the relation

A

$$\overline F = \frac{9}{2}\overline C + 32$$

B

$$\overline F = \overline C + 32$$

C

$$\overline F = \frac{9}{2}\overline C $$

D

$$\overline F = \frac{9}{5}\overline C - 32$$

ΔABC is an isosceles triangle and $$\overline {AB} $$ = $$\overline {AC} $$ = 2a unit, $$\overline {BC} $$ = a unit. Draw $$\overline {AD} $$ ⊥ $$\overline {BC} $$ , and find the length of $$\overline {AD} $$

A

$$\sqrt {15} $$ a unit

B

$$\frac{{\sqrt {15} }}{2}$$ a unit

C

$$\sqrt {17} $$ a unit

D

$$\frac{{\sqrt {17} }}{2}$$ a unit

The Hamiltonian of a particle is given by $$H = \frac{{{p^2}}}{{2m}} + V\left( {\left| {\overrightarrow {\bf{r}} } \right|} \right) + \phi \left( { + \left| {\overrightarrow {\bf{r}} } \right|} \right)\overrightarrow {\bf{L}} .\overrightarrow {\bf{S}} ,$$ where $$\overrightarrow {\bf{S}} $$ is the spin, $$V\left( {\left| {\overrightarrow {\bf{r}} } \right|} \right)$$ and $$\phi \left( {\left| {\overrightarrow {\bf{r}} } \right|} \right)$$ are potential functions and $$\overrightarrow {\bf{L}} \left( { = \overrightarrow {\bf{r}} \times \overrightarrow {\bf{p}} } \right)$$ is the angular momentum. The Hamiltonian does not commute with

A

$$\overrightarrow {\bf{L}} + \overrightarrow {\bf{S}} $$

B

$$\overrightarrow {{{\bf{S}}^2}} $$

C

$${L_z}$$

D

$$\overrightarrow {{{\bf{L}}^2}} $$

The value of the expression $$\frac{{{{\left( {a - b} \right)}^2}}}{{\left( {b - c} \right)\left( {c - a} \right)}} + $$ $$\frac{{{{\left( {b - c} \right)}^2}}}{{\left( {a - b} \right)\left( {c - a} \right)}} + $$ $$\frac{{{{\left( {c - a} \right)}^2}}}{{\left( {a - b} \right)\left( {b - c} \right)}}$$ = ?

A

0

B

3

C

$$\frac{1}{3}$$

D

2