Exploring Z Scores in Statistics

What is a normal distribution often referred to as?

• A skewed curve

• A parabolic curve

• A bell-shaped curve

• A linear graph

Which of the following human characteristics is NOT typically distributed in a normal curve?

• Height

• Weight

• Eye color

• Reaction time

In a frequency chart, what does the height of the curve represent?

• The number of people who scored a particular score

• The standard deviation

• The range of scores

• The average score

What is the mean IQ score on the Wechsler Intelligence Scale?

• 130

• 85

• 100

• 115

According to the empirical rule, what percentage of data falls within one standard deviation of the mean in a normal distribution?

• 99.7%

• 68%

• 50%

• 95%

What is a Z-score used to determine?

• The raw score of a test

• The number of standard deviations a score is from the mean

• The mean of a data set

• The range of a data set

If a person scores 115 on an IQ test with a mean of 100 and a standard deviation of 15, what is their Z-score?

• +2

• 0

• -1

• +1

Why are Z-scores useful in comparing different data sets?

• They provide the raw scores

• They calculate the mean

• They convert scores to a common scale

• They determine the range

In the example given, what was Amy's Z-score for her ACT score of 31?

• 0.5

• 2.1

• 3.0

• 1.25

Based on their Z-scores, who scored better in the example, Amy or Tim?

• Cannot be determined

• Amy

• Tim

• Both scored equally