Research On Which Factors Make People Inte l l igent

How Smart Are You?

Peng ZhangYuanchen WangMaricar Apuya

Lars HultChristopher Mongelli

Kexin Wang

How Smart Are You?

Introduction:

People always want to know if they are smart or not. There has always been controversy about the

determinants of a person’s intelligence level. In this case study we will study if gender, height,

weight, and brain size can be correlated with a person’s intelligence as measured by IQ.

How Smart Are You?

Procedure: Collecting Data Exploratory Analysis Running OLS Regression for All Variables Analyzing the Significant Variables Taking Out Insignificant Variables Rerunning New Regression Sequence Locating Endogenous Variables Conducting White’s Test for Heteroskedacity Analyzing Relationship between Significant Variables

and Explained Variables Conclusion

How Smart Are You?

Collecting Data

Data Reference: Willerman, L., Schultz, R., Rutledge, J. N., and Bigler, E.

(1991), "In Vivo Brain Size and Intelligence," Intelligence, 15, 223-228.

http://lib.stat.cmu.edu/DASL/Datafiles/Brainsize.html

How Smart Are You?

Collecting Data

Dependent Variable: FSIQ: Full Scale IQ scores based on the four Wechsler

(1981) subtests

Independent Variables: Gender: Male or Female VIQ: Verbal IQ scores PIQ: Performance IQ scores Weight: body weight in pounds Height: height in inches MRI Count: total pixel Count from the 18 MRI scans

How Smart Are You?

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Exploratory Data Analysis

How Smart Are You?

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How Smart Are You?

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Exploratory Data Analysis

How Smart Are You?

Running OLS Regression: All Variables

How Smart Are You?

Running OLS Regression: Drop Variable “Weight”

How Smart Are You?

Running OLS Regression: Drop Variable “Gender”

How Smart Are You?

Running OLS Regression: Drop Variable “Height”

How Smart Are You?

FSIQ = -1.239046537e-05*MRI_COUNT + 0.5467193408*PIQ + 0.5698886823*VIQ

Running OLS Regression: Drop Constant “C”

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Set VIQ as Dependent Variable

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Verbal IQ Scores Regressed Against Full Scale IQ Scores

How Smart Are You?

Set PIQ as Dependent Variable

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Performance IQ Scores Regressed Against Full Scale IQ Scores

How Smart Are You?

Conducting White’s Test for Heteroskedacity

Results: F-statistic is low (0.450243) The Dataset is thus Homoskedastic

How Smart Are You?

Analyzing Relationships between Significant Variables and Explained

Variables Through Graphs

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Full Scale IQ Scores Regressed Against Performance IQ Scores

How Smart Are You?

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Full Scale IQ Scores Regressed Against Verbal IQ Scores

How Smart Are You?

Conclusion

A person’s intelligence level does not rely on height, weight, or gender

It is, however, dependent on a person’s brain size (MIR_COUNT)

Verbal IQ Scores (VIQ), Performance IQ Scores (VIQ), and Full Scale IQ Scores (VIQ) are all endogenous variables.

References

Willerman, L., Schultz, R., Rutledge, J. N., and Bigler, E. (1991), "In Vivo Brain Size and Intelligence," Intelligence, 15, 223-228. http://lib.stat.cmu.edu/DASL/Datafiles/Brainsize.html