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In cluster analysis of microarray data– If Xi is the log odds value for gene X at time i, then for two genes X and Y and N observations, a similarity score is calculated. S(X,Y) is also known as the Pearson correlation coefficent. Xoffset and Yoffset can be the mean of the observations on X or Y, respectively, in which case is the standard deviation, or else Xoffset and Yoffset can be set to zero when a reference state is used. Which of the following best represents it?

In cluster analysis of microarray data– If Xi is the log odds value for gene X at time i, then for two genes X and Y and N observations, a similarity score is calculated. S(X,Y) is also known as the Pearson correlation coefficent. Xoffset and Yoffset can be the mean of the observations on X or Y, respectively, in which case is the standard deviation, or else Xoffset and Yoffset can be set to zero when a reference state is used. Which of the following best represents it? Correct Answer S(X,Y) = \(\frac{1}{N}\) ∑i=1,N . (Xi – Xoffset) (Yi – Yoffset)/ϕxQY

After values of S(X,Y) have been calculated for all gene combinations, the most closely related pairs are identified in an above-diagonal scoring matrix. The object of clustering is to identify genes that respond the same way to the environmental treatment. Each gene is compared to every other gene and a gene similarity score (metric) is produced.

Related Questions

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.
Which two of the following statements are true?  a) The sum of the deviations from mean (ignoring algebraic signs) is greater than the sum of the deviations from median (ignoring algebraic signs)  b) Standard deviation is independent of change of origin and change of scale  c) In a symmetrical distribution, mean deviation equals 4/5 of standard deviation  d) In a symmetrical and bell shaped distribution quartile deviation is 1/3 of standard deviation  Choose the correct answer from the options given below
How does number of observations influence overfitting? Choose the correct answer(s).Note: Rest all parameters are same
1. In case of fewer observations, it is easy to overfit the data.
2. In case of fewer observations, it is hard to overfit the data.
3. In case of more observations, it is easy to overfit the data.
4. In case of more observations, it is hard to overfit the data.
Consider the following statements regarding inspection and quality control: 1. Coefficient of variation is a relative measure of dispersion. 2. Standard deviation is the root mean square of the deviation of all the results. 3. Standard deviation is relative measure of dispersion. 4. Lower value of standard deviation indicates low degree of uniformity of observations. Which of the above statements are correct?
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 class of first year B. Tech. students is composed of four batches A, B, C and D, each consisting of 30 students. It is found that the sessional marks of students in Engineering Drawing in batch Chave a mean of 6.6 and standard deviation of 2.3. The mean and standard deviation of the marks for the entire class are 5.5 and 4.2, respectively. It isdecided by the course instructor to normalize the marks of the students of all batches to have the same mean and standard deviation as that of the entire class. Due to this, the marks of a student in batch C are changed from 8.5 to
Which of the following statements are true? a. The correlation coefficient is dependent on the choice of both origin and scale observations. b. The correlation coefficient is dependent on the units of measurements. c. The coefficient of correlation is the square root of the coefficient of determination. d. The zero value of the correlation coefficient cannot estimate the value of the dependent variable.
The values in one of the series in a bivariate data set are multiplied by a constant K, which of the following would change as a result of this? A. Karl Pearson's coefficient of correlation B. Standard deviation C. Covariance between the variables D. Rank correlation coefficient Choose the correct answer from the options given below:
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 mean of 5 observations is 60, the mean of 10 observations is 30 and the mean of 15 observations is 20. The mean of all the 30 observations is-