Carol Yepes / Getty Images
“You cant compare apples to oranges.”
Although the saying is cliche, the message behind it is clear.
Comparing two things that are completely different is hard to do.
Carol Yepes / Getty Images
You need a way to make the objects equal so it can give you a fair comparison.
Similarly, when analyzing numbers, experts have to find a way to make the numbers comparable.
This allows them to draw parallels between the information.
Finding the Z-score can help make sense of different types of data.
Finding the Z-score can help make sense of different types of data.
What Does a Z-Score Tell You?
A Z-score gives you a composite number for a specific set of data.
It helps provide standardized numbers for data that may otherwise be hard to compare.
Using the raw information to find the Z-score gave them the comparison tool that they needed.
Thats not exactly the case.
The Z-score and standard deviation are related but different concepts.
The standard deviation measures the spread or variability of the whole dataset.
A larger standard deviation indicates greater variability, while a smaller standard deviation indicates less variability, Brunner notes.
The Z-score gives a way to compare information.
The standard deviation tells you the difference between the two sets of information.
You then divide 15 by the number 3, because you have 3 separate values.
That gives you the number 5, which is the average of those numbers.
The standard deviation is a bit more detailed.
after you snag both values, you’re able to easily compute the z-score.
You would use the following formula: Z-score = (the initial data point mean)/standard deviation.
First, we find out the mean of this data set, which is 85.
Then you calculate the standard deviation, which is approximately 7.9.
Plugging the numbers into the formula, the Z-score is (90-85)/7.9, which equals 0.63.
If following the math is confusing, aZ-score calculatorcan help you find your answer.
Interesting information, but where is it applicable?
Z-Scores and IQ Testing
IQ test scores are highly prized for admission to certain clubs and organizations.
For some tests, you multiply the Z-score by 16 initially.
You then multiply 1.5 by 100, for an IQ score of 150.
Which Z-Score Indicates a Genius-Level IQ?
While this number can fluctuate, Brunner provides insight on a high-level z-score.
Some psychologists consider an IQ of 145 or above to be genius-level.
The z-score is (145 - 100) / 15 = 3 for this value.
The scores helped to create a uniform way to compare the information.
Experts say Z-scores can also help with tracking changes in patient’s depression andanxietylevels.
Z-scores serve as that beneficial tool on a variety of platforms.
American Psychological Assocation.APA Dictionary of Psychology.
Andrade C.Z scores, standard scores, and composite test scores explained.
Indian Journal of Psychological Medicine.
2021;43(6):555-557.
2019;14(8):e0220749.
39(1):9-37.
