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- A researcher found a significant correlation of .12 between gender (coded as 0 = ‘male’ and 1 = ‘female’) and number of friends at university. If the assigned values of gender were changed to 1 = ‘female’ and 2 = ‘male’, how would this affect the correlation? The strength of the relationship would become weaker The amount of variance explained by the relationship would increase It would become nonsignificantThe sign would change to become negative A researcher is trying to predict anxiety (measured on a 7-point scale) from exposure to stress (operationalised as the number of stressful life events participants can recall in the last week). She has found a correlation coefficient of r = .54 between anxiety and stress, with a standard deviation of 4.45 for anxiety and a variance of 17.21 for stress. What other information is needed to calculate b? The sums of squares of stressThe sums of products of anxiety and stress The covariance of anxiety and stressNo other information is…arrow_forwardIn Austria ,The amount of money spent on the restoration of a sanctuary and the distinct kangaroo populations present appeared to have negative correlations For investigation of this onserved assocaition ,what can a resecher do to begin his research 1Conduct an experiment 2Calculate the squares of coreealtion coefficient 3Calculate the least squares regression line 4 calculate the corelation coefficient Explain answer in 1 or 2 linesarrow_forwardWrite a clear conclusion regarding the association between height in inches and weight in pounds, using the multivariate model resultsarrow_forward
- Each year, marketing and information firm J.D. Power and Associates surveys new car owners 90 days after they have purchased their cars. The data collected are used to rate auto brands (Toyota, Ford, and others) on initial quality and initial customer satisfaction. USA Today reported both the number of manufacturing defects per 100 vehicles and a satisfaction score for all 33 brands sold in the United States.† A research group decides to compare the mean number of defects for 2 specific models of cars, A and B, made this year by taking random samples of 100 cars of each model. (a) After collecting the data, the research group calculates a 95% confidence interval to estimate the difference in population means. In this case, what is the population? all cars for models A and B that were produced this yearthe defects all cars made this yearthe 100 cars from each model (b) Suppose the calculated confidence interval is (84, 92) number of defects. What is the value of the point…arrow_forwardA team of researchers believe that millennials engage more in positive social media than baby boomers, including more likes, shares, and comments on posts that included positive language. After receiving consent from online participants, the researchers examined their history of Facebook activity and found that of the participants who engaged in at least 10 positive posts a week, 198 were millennials and 212 were baby boomers. Calculate χ 2 (chi-squared) to compare the proportion of millennials engaging in positive social media to the proportion of baby boomers.arrow_forwardA sociologist claims that the success of students in college (measured by their GPA) isrelated to their family’s income. For a sample of 20 students, the correlation coefficientis 0.40. Using the .01 significance level, can we conclude that there is a positive correlation between the variables?arrow_forward
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- Glencoe Algebra 1, Student Edition, 9780079039897...AlgebraISBN:9780079039897Author:CarterPublisher:McGraw Hill