Question 1
A random sample of 120 classrooms at a large university found that 70% of them had been cleaned properly. What is the standard error of the sample proportion?
◦ 0.042
◦ 0.082
◦ 0.028
◦ 0.046
◦ 0.458
Question 2
Doctors at a technology research facility randomly assigned equal numbers of people to use computer keyboards in two rooms. In one room a group of people typed a manuscript using standard keyboards, while in the other room people typed the same manuscript using ergonomic keyboards to see if those people could type more words per minute. After collecting data for several days the researchers tested the hypothesis H
0:
μ1 -
μ2 = 0 against the one-tail alternative and found a P-value of 0.22. Which is true?
◦ There's a 22% chance another experiment will give these same results.
◦ There's a 22% chance that people using ergonomic keyboards type more words per minute.
◦ None of these.
◦ There's a 22% chance that there's really no difference in typing speed.
◦ The people using ergonomic keyboards type 22% more words per minute.
The U.S. Long-Term Ecological Research (LTER) network.
Retinopathy. Illustration of a normal retina (left) and a diseased retina (right). The diseased reti
Research Methods
Sections of a Research Report
How to round numbers with significant digits