Question

A researcher with a reputation for yelling at graduate students wants to know how the seed yield of transgenic plants (that are constructed specifically with the objective of increasing seed yield) she is growing in a plot compares to that of the wild-type plants growing in another plot. The entire population of the wild-type plants have been characterized, but she only has enough funding to measure a sample of the transgenics. Her null hypothesis is that the average seed yield of the transgenics will not differ from the wild-type. Her graduate student secretly has an arm injury, and hasn't told her for fear of inciting the researcher's reputed wrath. Because his arm hurts, the graduate student inadvertently collects less heavy samples. This type of non-random sampling would increase the likelihood of committing a Type II error.
a. True
b. False

Answer 1

Answer:

False, it is a Type I error.

Explanation:

A Type II error is produced by not reject the null hypothesis when the alternative hypothesis is true, thereby the null hypothesis is false, but is erroneously not rejected. On the other hand, the Type I error may be caused by random variation in the data or errors in the research techniques to be used when the sample is obtained.  

In this case, it is a Type I error caused when the sample was obtained (i.e., due to the graduate worker collected less heavy samples).