Credentialism is another aspect of surveys and data that is highly suspect. The above ad for Trident was beaten into our heads on the television from the 1960's onward. But almost every word of this advertising phrase is suspect and can be picked apart. First of all is the phrase "dentists surveyed" - how were these dentists selected? Randomly? The ones who responded to a mailed survey? Telephone calls? What? What questions were asked? Was it "do you recommend sugarless gum for patients?" or was it "do you recommend Trident sugarless gum for patients?" There is a difference.
Even "hard" data can be soft, in many instances. For example, data on crime rates, which would seem to be pretty easy to acquire, based on crime reports taken by the Police, can be inaccurate as different police organizations classify crimes in different manners. Worse yet, some police departments are under political pressure to report fewer crimes so it makes it look like crime rates are going down when they may be going up, in that jurisdiction. The FBI had tried to quantify "hate crimes" and "mass shootings" but has had trouble, as not every police department keeps similar records or quantifies these things in the same manner.
Statistics, even if they are based on "good" data, can be misleading, if the conclusions drawn are inaccurate or simply not justified. For example, it is widely touted that the USA incarcerates more people than any other Western nation - indeed perhaps more than any nation, other than China. And while "people of color" make up about 30 percent of the United States' population, they account for 60 percent of those imprisoned.
Now, if you are a racist, you may use this data to argue that non-whites are morally inferior and more likely to commit crimes. However that is a conclusory statement based on correlation not causation.
If you are a Lefty, you might use this same statistic to say that the USA is fundamentally flawed and that the justice system is "racist". There may be a nugget of truth to that, when you consider the same judge in Texas who sentenced the "affluenza" teen to 10 years of probation for killing four people, sentenced a black teen to 10 years in jail for a very similar crime.
On the other hand, you might note that poverty rates among blacks are higher, as a percentage, among whites, and that impoverished people tend to commit crimes more often, get caught more often, get prosecuted more often, get convicted more often, and get longer jail sentences.
But you might also note there are more white "poor" people in the USA, simply because whites outnumber non-whites by more than 2 to 1. So if the poverty argument is to make any sense, there would be more white people in jail than blacks. Also, note from the chart above, that poverty rates have declined among minorities, since the 1960's. I am not aware also whether black incarceration rates have gone up or down in recent years, accordingly.
So what is the correct answer? I think there is more than one. I don't think non-whites are morally inferior to whites. However, in many minority communities, a culture of criminality - celebrated in movies, music, and our culture - has been created in recent decades. While there are Black gangs and Hispanic gangs (e.g., crips and bloods) there are few nationally-known white gangs of similar stature.
And the reason for this is that white poverty tends to be rural poverty, and thus the gang mentality and the culture of criminality that is prevalent in cities tends not to take hold in the country. Perhaps there is a survey that validates this. Perhaps no one has bothered to ask. Do poor white kids who grow up in the inner city end up in jail more often than poor white kids who live in a trailer in the country and go to the evangelical church? I suspect so.
(That is one reason I say, as a personal choice, to get the fuck out of the ghetto any way you can. If you live in such an impoverished, inner-city neighborhood where criminality and criminals are celebrated, it is only a matter of time before you are a victim of a criminal, you become a criminal, or one of your children becomes a criminal. Why people stay in shitty neighborhoods is beyond me. And no, it is often not a matter of what you can "afford" but choosing to have consumer goods over a good address.)
So that is one aspect. Racism is indeed another, but maybe not as strong at the first. Black offenders are given longer sentences and prosecuted more often than white ones. While often this is because the white offender has a better lawyer, it may also be true that there is an institutional bias. But I don't think that explains it entirely, as the prosecution rate of minorities in cities where the arresting officer, the prosecutor, and even the judge are likely to be minorities as well, seems to be just as high.
And the third answer is, as shown in the chart above, the increased incarceration rates in the US. The "three strikes and you're out" law, which was part of our "get tough on crime" program, put people into jail who in the past would be through a revolving door of prison again and again. You may be too young to remember this, but in the late 1970's crime rates soared (again, see the chart above) and places like New York City were basically unsafe. Times Square was a place where you got mugged. The New York Subway was like a graffiti-covered urinal - and a good place to get mugged as well.
And another part of this was the "war on drugs" which was ramped up as the crack epidemic (and now the meth epidemic) swept the nation. And yes, a lot of drugs were dealt in the inner cities (and was easier to detect and prosecute in the inner cities). It will be interesting to see how legalization of marijuana will affect these incarceration rates, over time.
But the main thing is, what conclusion you draw from the data depends a lot upon your preconceived notions. If you are a racist, you view this as proof of your beliefs. If you are a leftist, you view this as proof that the USA is a horrible racist place.
If you are a realist, on the other hand, maybe you see the conclusion as more complex and nuanced and based on a number of inter-related and unrelated factors. Conclusions and data are two different things, and we can (and do) routinely draw the wrong conclusions from data, because we have a preconceived notion that we want to validate. We all do this.
And speaking of incarceration rates, while we lead the world in locking people up (other than China, apparently), our crime rates have been dropping for decades. Are the two related? Are crime rates dropping because we are locking up the bad guys? Or it is because we are not counting crimes as much as we used to (for political reasons)? It is an interesting question, I don't have a real answer, other than whether or not someone should be released from jail should depend on what crime they were convicted of, not some overall statistics. People are not statistics, and should not be treated as such.
P.S. - and bear in mind that you are not a statistic. Regardless of what your friends or family or socioeconomic group is doing, you don't have to make the same choices.