Introduction to Statistics in Psychology: PSY 201 - Department of ...

PSY 201 4
(14) Numerous studies have shown that IQ scores have been increasing, generation by generation,
for years (Flynn, 1984, 1999). The increase is called the Flynn Effect, and the data indicate that the
increase appears to be about 7 points per decade. To demonstrate this phenomenon, a researcher
obtains an IQ test that was written in 1980. At the time the test was prepared, it was standardized
to produce a population mean of µ = 100. The researcher administers the test to a random sample
of n = 16 of today’s high school students and obtains a sample mean IQ of X = 121 with s = 6.32.
Is this result sufficient to conclude that today’s sample scored significantly higher than would be
expected from a population with µ = 100 Use a one-tailed test with α = 0.01.