Meteorologists add the wind-chill factor to their winter weather forecasts to make the actual temperature seem worse than it is.
Likewise, when the FBI reported on Sunday that serious crime had declined slightly for the fourth year in a row, it was still making the statistics sound worse than they actually were.That's because the government tends to exaggerate the violent nature of crime.
According to the Justice Department's Bureau of Justice Statistics, less than a third of the 6.6 million violent crimes committed in the United States in 1992 - the last year for which statistics are available - resulted in injury. Most of the victims suffered only minor cuts, scratches or bruises.
About 20 percent of them needed minor medical care; 7 percent went to emergency rooms. Only 1 percent of the victims were hurt seriously enough to require hospitalization.
The incongruity arises because of the way the law defines violent crime. For example, aggravated assault is defined as either intentionally causing serious bodily harm or using a weapon to threaten or attempt to cause bodily harm.
Fortunately, most aggravated assaults fall into the last category. Most victims are never touched by the offender.
The same holds true for armed robbery. In 1992, less than a third of robbery victims were injured and only 3 percent required medical treatment. Less than half of armed robbers displayed guns, and those who did were less likely to injure victims than robbers who didn't show guns.
Yet the FBI has a tendency to worry people unnecessarily, even when it has good news. Last year it announced that 53 percent of all homicides were committed by strangers, and that for the first time all Americans had a "realistic" chance of being murdered.
But to arrive at these troubling figures, the FBI considered all unsolved homicides, including drug-related killings, as homicides committed by strangers, thus creating an impression that murder was becoming increasingly random.
The push for "three strikes" laws has also helped exaggerate the violent nature of crime. By combining disparate categories of offenders under such categories as "violent," "persistent" and "serious," these laws fail to distinguish the habitual petty criminal from more vicious felons.
Under federal law and the laws of California and Washington State, drug trafficking, burglary and prostitution are considered violent crimes.
An American's chances of being murdered are no greater today than they were two decades ago. It was 1 in 10,500 in 1993 compared with 1 in 10,200 in 1974. For those aged 50 and over, the risk has dropped sharply.
The notable exception is the homicide rate among black male teenagers. It has tripled in the past decade.
This is not to say that violent crime is not a serious problem or to discount the sufferings of the victims. But by offering a more accurate description of violent crime, the government can help calm fears and encourage a more rational discussion of crime.