2048 There is evidence that cytotoxic T lymphocytes T cells

(20.48) There is evidence that cytotoxic T lymphocytes (T cells) participate in controlling tumor growth and that they can be harnessed to use the body\'s immune system to treat cancer. One study investigated the use of a T cell-engaging antibody, blinatumomab, to recruit T cells to control tumor growth. The data below are T cell counts (1000 per microliter) at baseline (beginning of the study) and after 20 days on blinatumomab for 6 subjects in the study. The difference (after 20 days minus baseline) is the response variable.

Baseline0.040.020 0.02 0.43 0.39

After 20 days00.370 0.15 1.02 0

Difference-0.040.350 0.13 0.59 -0.39

Do the data give evidence at the 2% level that the mean count of T cells is higher after 20 days on blinatumomab?

The test statistic is t =____ (±0.001)

No

HINT: We want to know if the mean count is higher after 20 days on blinatumomab. That means we are testing H0: D=0 (our data are the differences after minus bfore). If the mean count is higher, the differences should be positive, so we have Ha: D>0. Perform a t test using the differences as your data.

Solution