Don2 (Don1 Revised)
Contributor
Asked and answered. In brief: statistically, it is pretty much impossible for it to be due to chance. So it's either discrimination or some other factor that is relevant to admissions and where blacks and Hispanics best whites and Asians. Nobody here has even attempted to identify such a a factor, much less provide any evidence for it. So, discrimination is a logical conclusion.I don’t see how you can actually know that is in fact an accurate statement.
I actually did and mentioned this plausible factor several times. I even did so recently in a post to you. You did not reply. Perhaps you missed it. It happens.
I shared earlier about who actually works in underserved areas (which includes rural areas): Asians and Whites were at the bottom. Native Americans were the highest in all underserved locations, followed by Blacks and Hispanics. So theoretically, if a demographic's acceptance rate is tied to fulfilling a public good, the formula isn't just about scores. It looks more like: Acceptance rate = f(MCAT, GPA, Mission Fitness)
Of course, admissions committees look at far more than just this, but I am bringing it up because it is a significant explanatory variable that behaves roughly in an opposing direction to the MCAT mean differences across your division of groups.
Emphasis added. "earlier" is in reference to another post.
This blurb comes from the second study I linked, which looks at practice patterns nationally:
There are also significant difference in geographic distribution across primary care specialties with family physicians and general practitioners overall having higher proportion practicing in HPSA, MUA/P, and rural areas in the study cohort (see Figures 2 through 4). Among primary care physicians as a whole, substantial racial/ethnic differences exist in how they distribute geographically (p < .0001). Black, Native American, and Hispanic groups have higher proportions practicing in HPSA, MUA/P, and rural areas compared with White primary care physicians and the Asian group, who have smaller proportions practicing in these areas. Within each primary care specialty, significant differences by race and ethnicity (p < .0001) also exist across the geographies. Black, Native Americans, and Hispanic groups have higher proportions practicing in HPSA and MUA/P than their White peers in all three primary care specialties. Native American primary care physicians have the highest proportion practicing in rural areas, whereas White primary care physicians have higher proportions practicing in rural areas compared with Black or Hispanic primary care physicians. In particular, the Native American primary care physicians have high proportions practicing in all three underserved areas. The Asian primary care physicians also have a substantial number practicing in these areas, but their proportions practicing in these areas are much smaller compared with any other racial/ethnic group.
Let's parse the findings from that paragraph to see how the demographic groups actually rank in fulfilling this public good.
First, looking at the overall distribution across all underserved areas in aggregate, the study establishes a clear baseline:
Next, it breaks this down into three specific geographic categories (HPSA, MUA/P, and Rural) to reveal the hierarchy:"Black, Native American, and Hispanic groups have higher proportions practicing in HPSA, MUA/P, and rural areas compared with White primary care physicians and the Asian group..."
- HPSA & MUA/P (2 of the 3 categories): Native American, Black, and Hispanic physicians practice here at higher rates than White physicians.
- Rural (1 of the 3 categories): Native Americans still practice here at the highest rate, but White physicians practice in rural areas at higher rates than Black and Hispanic physicians.
If we score these groups based on their aggregate propensity to fill needed positions in underserved areas, the ordinal ranking is undeniable:
- Native Americans: Highest in 3 out of 3 categories.
- Blacks & Hispanics: Higher than Whites in 2 out of 3 categories (and higher overall).
- Whites: Higher than Blacks and Hispanics in only 1 out of 3 categories (Rural).
- Asians: Lowest in all categories.
Part of an individual applicant's admissions packet includes secondary essays and interviews where the candidate is queried on their willingness and historical commitment to working in these areas. (I most recently submitted an example of some questions to candidates in North Dakota). While this is evaluated on a strictly individual basis, if students are honest about their career trajectories, there will--as a logical consequence--be aggregate differences in this kind of "mission fitness."
To repeat: aggregates are not individuals. But if we look at the aggregates as you have been doing, there is a very real, non-nefarious explanatory variable that operates in the reverse direction to the MCAT averages. In aggregate, Native Americans would score at the top for this mission fitness, Asians would be at the bottom; Blacks and Hispanics would be tied for second, and Whites would be third.
Therefore, let's use this split function as a rough estimate:
f(mission fitness) = { 9 if NA; 7 if Black or Hispanic; 5 if White; 3 if Asian }
We do not have this data for Native Hawaiian (very very rare medical students) nor new categories like Middle Eastern nor multiple ethnicities/races.
We can explore a best fit to deal with here in a simulation of admission criteria:
Acceptance rate = A x MCAT mean of applicants + B x GPA mean of applicants + C x mission fitness
Using the adjusted non-Puerto Rican numbers for the Hispanic cohort alongside the rest of the aggregate applicant data (after also fixing the Black acceptance rate), we have:
- NA: 500.7 MCAT, 3.51 GPA, 9 Mission (Acceptance Rate: 40.74%)
- Black: 498.1 MCAT, 3.43 GPA, 7 Mission (Acceptance Rate: 31.02%)
- Hispanic: 501.5 MCAT, 3.53 GPA, 7 Mission (Acceptance Rate: 36.46%)
- White: 508.0 MCAT, 3.72 GPA, 5 Mission (Acceptance Rate: 47.17%)
- Asian: 508.8 MCAT, 3.72 GPA, 3 Mission (Acceptance Rate: 44.46%)
Acceptance Rate = -1183.13 + 2.50(MCAT) - 13.27(GPA) + 2.23(Mission Fitness)

The R2 is 0.988. This means the model mathematically explains nearly 99% of the variance in acceptance rates between these groups.
Caveat: "With three parameters I can fit an elephant, with one more I can make him wiggle his tail."
We should naturally expect an astronomically high R2 here. When you use four parameters (an intercept plus three variables) to model just five aggregate data points, the math will inevitably draw a line that perfectly intersects almost every point. (You can also see the statistical noise of overfitting in the coefficients themselves--the GPA multiplier actually turns negative purely because it is so heavily correlated with the MCAT). With so little aggregate data and so many variables, the model overfits by design.
Therefore, it is important to note this is a test to explore plausibility and confirm that this is a plausible explanation, not to provide a definitive proof. We cannot really see what happens behind the scenes. In reality, perhaps some people are implementing something nefarious. Perhaps others are being lazy and using race as a proxy for these public goods. While others may be doing the rigorous math of using criteria in admissions that includes mission fitness, and we are simply observing the results in the aggregate.
To add--we still do not know how much of the differences are due to matriculating to different schools with different thresholds. We observed how much Puerto Rico can affect the numbers. There isn't much data on the matriculation side of this.

