Using data from twelve European countries, it has been calculated that the correlation between the level of car ownership and the number of road deaths is 0.73. Which of the statements shown follow from this?(i) High levels of car ownership cause high levels of road deaths(ii) There is a strong relationship between the level of car ownership and the number of road deaths(iii) 53% of the variation in the level of road deaths from one country to the next can be explained by the corresponding variation in the level of car ownership(iv) 73% of the variation in the level of road deaths from one country to the next can be explained by the corresponding variation in the level of car ownership
A、(i) and (ii) only
B、(i) and (iii) only
C、(ii) and (iii) only
D、(ii) and (iv) only
A、(i) and (ii) only
B、(i) and (iii) only
C、(ii) and (iii) only
D、(ii) and (iv) only
【参考答案及解析】
(i) High levels of correlation do not prove that there is cause and effect. (ii) A correlation coefficient of 0.73 would generally be regarded as indicating a strong linear relationship between the variables. (iii) The coefficient of determination provides this information and is given by squaring the correlation coefficient, resulting in 53% in this case. (iv) The coefficient of determination provides this information and not the correlation coefficient. Remember that you must square the correlation coefficient in order to obtain the coefficient of determination.Statements (ii) and (iii) are relevant and the correct answer is therefore C.
(i) High levels of correlation do not prove that there is cause and effect. (ii) A correlation coefficient of 0.73 would generally be regarded as indicating a strong linear relationship between the variables. (iii) The coefficient of determination provides this information and is given by squaring the correlation coefficient, resulting in 53% in this case. (iv) The coefficient of determination provides this information and not the correlation coefficient. Remember that you must square the correlation coefficient in order to obtain the coefficient of determination.Statements (ii) and (iii) are relevant and the correct answer is therefore C.