Question

A new idea for treating advanced melanoma, the most serious kind of skin cancer: Genetically engineer white blood cells to better recognize and destroy cancer cells, and then infuse these cells into patients. The subjects in a small initial study of this treatment were 1111 patients whose melanoma had not responded to existing treatments. One question was how rapidly the new cells would multiply after infusion, as measured by the doubling time (in days). The doubling times are provided:

1.41.4

1.01.0

1.31.3

1.01.0

1.31.3

2.02.0

0.60.6

0.80.8

0.70.7

0.90.9

1.91.9

To access the complete data set, click the link for your preferred software format:

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(a) Examine the data. Is it reasonable to use the ?t procedures?

a.)No, because the distribution is clearly skewed.

b.)Yes, but a larger data set would be better.

c.)No, because there are clear outliers.

d.) Yes, there are no concerns with the sample data.

(b) Give a 90% confidence interval for the mean doubling time. (Enter your answer rounded to four decimal places.)

lower bound days:

upper bound days :

Are you willing to use this interval to make an inference about the mean doubling time in a population of similar patients? Select all statements that are correct.

A larger sample size would be preferable.

The standard deviation is too large for a sample of this size.

The interval is not a good estimate of mean doubling time.

This interval could serve as a preliminary estimate of the population mean ?μ .

Answer 1