Question

QUESTION 3 [20M] Given the data below, where x is the number of hours playing online game, y is the student's class test marks Student Variable 10 20 12 40 80 60 50 a) Name the two most popular correlation coefficients. b) Which one will you use for the data presented in the above table and why? c) Calculate the correlation coefficient, r d) Make a scatter plot of the data. From the plot, does the word linear really provide the most effective description of the relationship between x and Based on answers in (b) and (c), what is the value of r suggests about the relationship between the numbers of hours studied per day by a particular student and the student's class test marks e)

Answer 1

a) 1.pearson product-moment correlation coefficient

2.Spearman's rank correlation coefficient.

b)We use 1 pearson correlation coefficient because we want to see linear linearship between variable X and variable Y.

c)I computed correlation coefficient using EXCEL.

1=> Enter the data in excel spreadsheet as given in omage below.

2=> use the formulae,

=Corr(array1,array2)

output is on screen.

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d) Now we draw scatter plot using excel.

1=> Enter data in excel as given above.

2=> go to insert option and click on SCATTER

and select type and click ok then output is on screen.

e) r= -0.69404

There is a strong downhill (negative) linear relationship.

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