CompTIA Strata *In the event that you fail your first (1st) attempt to pass any CompTIA certification examination, CompTIA does not require any waiting period between the first (1st) and second (2nd) attempt to pass such examination.
See normal distribution for the bell curve in statistics. The Bell Curve is a controversial, best-selling 1994 book by Richard J. Herrnstein and Charles Murray exploring the role of intelligence in American life. The authors became notorious for the book's discussion of race and intelligence in Chapters 13 and 14.
Selection pressures usually cause a narrowing of the bell-shaped curve distributions of traits in populations. The genes interact with environmental influences, which also have a certain degree of randomness. The result is a massive combined randomness. It is this massive randomness that leads to the bell-curve distribution. The bell curve itself is not random at all, which is a fascinating aspect of this phenomenon. From âchaosâ comes âorderâ. A bell curve is a well-defined curve that is associated with a function, the probability density function. The underlying mathematical reason for the bell shape is the central limit theorem. The genes are combined in different individuals as combinations of alleles, where each allele is a variation (or mutation) of a gene.