Which T test should you use?
1. An early childhood teacher wants to compare Peabody Picture Vocabulary Test (PPVT) scores of economically depressed and advantaged students; if there are no differences she will treat them all the same. If there is a significant difference she will make adaptations in her class.
T test for correlated data? Or T test for uncorrelated? (choose)
Data
Econ. Dep PPVTs Advantaged PPVTs
11 83
14 77
9 75
15 79
13 60
23 55
22 57
19 52
21 62
18 53
17
14
Is there enough difference in the disadvantaged and "normal" childrens' verbal abilities to consider them different, i. e., make modifications?
2. Mrs. T is writing a proposal to a private foundation trying to get funding for computers for her physical science classroom. Because of prevailing conditions she is not going to be able to pledge cooperation from any classroom other than her own. The RFP calls for a research design which demonstrates the effectiveness of the innovation in a realistic classroom situation. They will give $30, 000 in computers to the classroom that conducts this demonstration. In her proposal, she decides to measure her students' physical science knowledge before using the computers which the foundation will hopefully supply and after using the computers for four months.
Which T test? Dependent? Independent? Pre-test science scores Post-test scores
37 77
40 80
26 76
30 68
34 70
38 82
36 88
32 74
Do the above data show that using the computers were effective in promoting achievement in physical science?
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