An engineer believe he has designed an improved light bulb. The previous design
ID: 3264314 • Letter: A
Question
An engineer believe he has designed an improved light bulb. The previous design had an average lifetime of 1200 hours. Using a sample of 2000 of these new bulbs, the average lifetime of this improved light bulb is found to be 1201 hours. Although the difference is quite small, the effect was statistically significant at the 0.05 level. Suppose that, in fact, there is no difference between the mean lifetimes of the previous design and the new design. Which of the following statements is true?
a. A type I error was made
b. A type II error was made
c. Both type I and type II errors were made
d. No error was made
Explanation / Answer
The result is found to be statistically significanct that means we concluded that the light bulb lifetime has improved whereas in actual there was no difference.
So,
Type I error was made.
Option A is correct.