Question

GMy Notes Ask Your Teacher 5 1/4 points Previous Answers PriviteraStats3 15.E.019. A researcher measures the relationship between the number of interruptions during a class and time spent "on task" (in minutes). Answer the following questions based on the results provided. Number of Interruptions Time Spent "On Task 10 15 38 29 Part (a) Compute the Pearson correlation coefficient. (Round your answer to three decimal places.) Part (b) Multiply each measurement of interruptions times 3 and recalculate the correlation coefficient. (Round your answer to three decimal places.) Part (c) Divide each measurement in half for time spent "on task and recalculate the correlation coefficient. (Round your answer to three decimal places.) Part (d) True or false: Multiplying or dividing a positive constant by one set of scores (X or Y) does not change the correlation coefficient. Note: Use your answers in (a) to (c) to answer true or false. OTrue Fase Additional Materials eook My Notes 6 PriviteraStats3 15.E.021. Ask Your Teacher 1/2 points Previous Answers A researcher records data to analyze the correlation between scores on two surveys that are supposed to measure the same construct. Using the hypothetical data given in the following table, compute the Pearson correlation coefficient. (Round your answer to three decimal places.)

Answer 1

5)

a)

x	y	(x-x̅)²	(y-ȳ)²	(x-x̅)(y-ȳ)
10	15	7.56	100.00	-27.50
5	38	5.06	169.00	-29.25
9	18	3.06	49.00	-12.25
5	29	5.06	16.00	-9.00

	ΣX	ΣY	Σ(x-x̅)²	Σ(y-ȳ)²	Σ(x-x̅)(y-ȳ)
total sum	29	100	20.75	334.000	-78.000
mean	7.250	25.000	SSxx	SSyy	SSxy

correlation coefficient ,    r = Sxy/√(Sx.Sy) =   -0.937

b)

	ΣX	ΣY	Σ(x-x̅)²	Σ(y-ȳ)²	Σ(x-x̅)(y-ȳ)
total sum	87	100	186.75	334.000	-234.000
mean	21.750	25.000	SSxx	SSyy	SSxy

correlation coefficient ,    r = Sxy/√(Sx.Sy) =   -0.937

c)

	ΣX	ΣY	Σ(x-x̅)²	Σ(y-ȳ)²	Σ(x-x̅)(y-ȳ)
total sum	29	50	20.75	83.500	-39.000
mean	7.250	12.500	SSxx	SSyy	SSxy

correlation coefficient ,    r = Sxy/√(Sx.Sy) =   -0.937

d) TrUE