It Is Known That a Particular Laboratory Task Takes the Average

Essay

It is known that a particular laboratory task takes the average person 2.5 seconds. A researcher was interested in whether older people are slower (take longer)on this task. The researcher tested 30 randomly selected 80-year-olds. Their mean time was 2.7 seconds, with an estimated population standard deviation of 1.4 seconds. What should the researcher conclude (use the .05 level)?
a. Use the five steps of hypothesis gathering.
b. Sketch the distributions involved.
c. Explain what you did to a person who is familiar with hypothesis testing with a known population variance and a single sample, including understanding decision errors, effect size, and power, but knows nothing about t tests of any kind.