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A study looks at the average wait times (minutes) in hospital Emergency Rooms before and after a training programming for staff. Below is the data that was collected (note: N/A means data is missing because the hospital failed to report it).   ER Wait Times (in mins) Pre-Training Post-Training Hospital 1 15 14 Hospital 2 10 11 Hospital 3 27 26 Hospital 4 43 28 Hospital 5 37 27 Hospital 6 17 15 Hospital 7 28 N/A Hospital 8 12 15 Hospital 9 19 11 Hospital 10 N/A 30   What are the degrees of freedom for this test?

If you found t(70) = 1.70, how many participants were there?

A study looks at several companies’ profits before and after the introduction of a environmentally friendly initiative. Below is the data that was collected (note: N/A means data is missing because the company failed to report it).   Profit of Companies (in millions of dollars) Pre-Initiative Post-Initiative Company 1 12.7 N/A Company 2 10.4 12.5 Company 3 9.5 8.5 Company 4 8.3 8.4 Company 5 8.6 8.9 Company 6 N/A 10.7 Company 7 6.9 6.5 Company 8 7.7 N/A Company 9 10.1 9.8 Company 10 11.8 12.1 Company 11 N/A 14.5 Company 12 8.9 9.7   What are the degrees of Freedom for this test?

Bill creates a new kind of battery and he wants to compare it to Energizer. He randomly assigns 10 of his friends to test his new batter and 10 of his friends to test energizer batteries. His friends then rate measure the number of hours the batteries run. With his new battery, his friends report an average of [a] hours of battery life, with a standard deviation of [a2]. With Energizer his other friends report an average of [b] hours of battery life, with a standard deviation of [b2].    What is the effect size of the difference between these two batteries? (Write your answer below, to two decimal places as a positive value; sign doesn’t matter)

High school attendance study A high school conducts an experiment to test if there is a difference between the number of times their students are absent in the fall compared to the winter months.   You have data for the following 5 students:   Data STUDENT FALL WINTER 1 2 1 2 0 2 3 1 2 4 2 2 5 0 3   What do you conclude about this school’s absences? (Assume standard

Manny creates a new kind of energy drink and he wants to compare it to Red Bull. He randomly assigns 10 of his friends to drink his new energy drink and 10 of his friends to drink Red Bull and then asks them rate their energy on a scale from 1-10. With his new drink, he finds an average energy rating of [a], with a standard deviation of [a2]. With Red Bull his friends report an average energy rating of  [b], with a standard deviation of [b2].    What is the effect size of the difference between these two energy drinks? (Write your answer below, to two decimal places as a positive value; sign doesn’t matter)

A researcher tells some participants that they scored low on an intelligence test while she tells others they scored high on the intelligence test. Although she never actually graded the tests, she finds that those told they scored low rated their abilities much lower than those told they scored high. What is the best test to analyze the results of this study?

Calculate the effect size of your test. What should you interpret based on the effect size of Ad Types on Persuasion?

For a two-tailed independent samples t-Test, what specific critical value do we need to overcome at the p < 0.05 level for a study with 26 participants per condition?

For a one-tailed dependent samples t-Test, what specific critical value do we need to overcome at the p < 0.01 level for a study with 28 participants?