Assignment 4 Chapter 10 10.1. In a t test for a single sample , the sample ' s mean is c o m par ed to the population . 10.2. When we use a paired-samples t test to compare the pret es t and p ostt est scores for a group of 45 people, the degrees of freedom ( df ) ar e _____. 10.3. If we conduct a t test for independent samples , and n1 = 32 and n2 = 35, the degrees of freedom (df) are _____. 10.4 . A researcher wants to study the effect of college education on p eo p le's earning by comparing the annual salaries of a randomly - selecte d g ro up of 100 college graduates to the annual salaries of 100 randoml y-selected group of people whose highest level of education is high schoo l. To compare the mean annual salaries of the two groups , th e resea r cher should use a t test for ______. 10.5. A training coordinator wants to determine the effectiveness of a program that makes extensive use of educational technology when t raining new employees. She compares the scores of her new emplo yees who completed the training on a nationally-normed test to th e me a n s c ore of all those in the country who took the same test. The a p pro p riate statistical test the training coordinator should use for h er analysis i s the t test for ______. 10 . 6. As part of the process to develop two parallel forms o f a q u es t io nn aire , the persons creating the questionnaire may admin i st e r b o th f or ms to a group of students, and then use a t test for ______ s a mpl es t o com p are the mean scores on the two forms . Circle the correct answer: 10.7. A difference o f 4 points between two homogeneous group s is lik e ly to be more/less statistically significant than the s ame d i ffe r e n ce (of 4 points) between two heterogeneous groups , when all fou r g r o up s are taking completing the same survey and have appro x im a tel y t h e same number of subjects. a. 10.8. A difference of 3 points on a 100-item test taken b y t w o g rou ps is likely to be more/less statistically significant than a difference of 3 po i nt s on a 30-item test taken by the sa m e t w o g r oups. 10.9 When a t test for paired samples is u s ed to c ompare th e p re t est an d the posttest means , the number of pretest scores i s the same as/different than the number of po s t-t e st scor e s. 10.10. W hen w e w ant to compar e w h e th e r female s ' scor es on th e G MAT are di fferent f rom males' scores , we should use a t test for paired samples/independen t samples . 10 .11 In studi e s w h e re the alte r nati ve ( r es ear c h ) h y poth es i s i s directiona l , t h e critical va lu es for a one tailed test/two-tailed test should b e us ed t o d e t erm i ne the l e vel o f signi fi cance (i . e. , the p va lue). 10.12 W h e n t h e alt e rnati ve h y poth e si s is: H A : u1 =u2 , the c ri ti ca l v alu es for o.