[Solved] What is the difference between expressive and receptive language disorders? Sexual Practices: Activities or behaviors that individuals engage in as part of their sexual life or to achieve sexual pleasure. Variability: The extent to which data points in a statistical distribution or dataset differ from each other and from the average or mean. Alfred Kinsey: An American biologist and sexologist, one of the pioneers in researching human sexuality in the mid-20th century, noted for his Kinsey Reports. Sexual Activity: Behaviors that involve sexual intimacy or erotic stimulation between individuals.