# Is negative a researcher wanted to know if the order

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is negativeA researcher wanted to know if the order in which runners finish a race is correlated with their weight. She conducts an experiment and the data are given below.Finishing order12345
Weight (lbs)11011411210811What is the appropriate correlation coefficient for these data? RhoIn a perfect relationship, _________. all the points fall on the lineYcan be most accurately predicted from Xif the correlation between Xand Yis _________. 0.98Which of the following is (are) not correlation coefficients? they all are correlation coefficientsThe closer the points on a scatter diagram fall to the regression line, the _________ between the scores. higher the correlationWhen a correlation exists, lowering the range of either of the variables will _________. lower the correlationAfter several studies, Professor Smith concludes that there is a zero correlation between body weight and bad tempers. This means that _________. a person with a bad temper may be heavy or skinnyWhich of the following is(are) correct interpretation(s)of correlation? Correlation _________. a and cIn a positive relationship, _________. as Xincreases, Yincreases and as Xdecreases, YdecreasesIn order to properly use rho, the variables must be of at least _______ scaling. Ordinal
A traffic safety officer conducted an experiment to determine whether there is a correlation between people’s ages and driving speeds. Six individuals were randomly sampled and the following data were collected.Age202545466065Speed (mph)604755384535The value of Pearson requals _________. 0.70In the equation Y = bX+ a, Xand Y, bis _________. a constant and slope of the lineRho is used _________. when one or both variables areonly of ordinal scalingWhat is the value of the Spearman rank order correlation coefficient (rho) for the following pairs of ranks?0.50Causation implies correlation. TrueIf one calculates rfor raw scores, and then calculatesron the zscores of the same data, the value of rwill _______. Stay the same
Correlation implies causation. FalseThe correlation coefficient between heights from the ground of two people on the opposite ends of a seesaw would be _________. 1.0Which of the following statements is true? Causation implies correlation.You have conducted a brilliant study which correlatesIQ score with income and find a value of r= 0.75. At the end of the study you find out all the IQ scores were scored 10 points too high. What will the value of rbe with the corrected data? rwill remain the sameIf two variables are ratio scaled and the relationship is linear, what type of correlation coefficient is most appropriate? Pearson rIn an imperfect relationship, _________. a relationship exists, but all of the points do not fall on the lineIf one takes a sample of pairs of points over a narrowrange of Xor Yscores, what effect might this have onthe value of r? reduce rIt is possible to compute a coefficient of correlation if one is given _________. two sets of measurements on the same individualsIn a negative relationship, _________. as Xincreases, Ydecreases
Pearson rcan be properly used on which of the following type(s) of relationships? Linear
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