Statistics problems

1 . T as the test statistic is appropriate for the problem because the actual population variance is not known . Only an estimator , s , or the sample standard deviation can be determined . However , independent t-test is not applicable because they are dealing with the same subjects , for the 2 scenario (the before and after . It must be a paired t-test . The past data must be compared to the present data for each dam , not their averages as a group . The use of historical data is the most convenient way for this study because a

designed experiment will be costly and impractical . However , T-test can only determine correlation . That is the researchers can only conclude whether the steel head population and the presence of the dam are correlated not if the dams cause the changes in the population . Assuming that the test is applicable for this problem , the Levene 's Test says that we can assume equal variances because the value 1 .00 under "Sig " is less than 0 .05 . A significant level of 0 .05 level can be used in the interpretation of the result since it is a two-tailed test . The

value is 1 .0 in the result which is greater than 0 .05 so we can conclude that there is no significant difference on the two means thus , correlation is verified

2 . The p-value of 0 .001 is small enough to conclude that indeed weather affects the time spent for studying . The recommendation is questionable because it is...