Answer to Question 1
A hypothetical construct is a theoretical idea that refers to something that can't be observed directly. For example, arousal involves a subjective feeling of being aroused, which cannot be directly observed. In order to use such an idea scientifically, it must be defined in terms of observable indicators, even if these indicators do not define the idea completely. These observable indicators are the operational definition. In the case of arousal, observable factors such as penile circumference and vaginal engorgement are used as indicators of arousal. If these indicators turn out to be related to other indicators of arousal, such as the person's subjective report, then the indicators are said to have construct validity. This means that they are thought to be valid, if incomplete, indicators of the hypothetical construct.
Answer to Question 2
The NHSLS surveyed 3,500 men and women between the ages of 18 and 59 throughout the United States. Some key findings from the study are that masturbation is relatively common in men and women, that virtually all men and women experienced vaginal intercourse at some point in their lives, that most men and women had engaged in oral sex, and that most sexual activity occurs in the context of monogamous relationships. Also of note, there is a very large difference between men and women with regard to the experience of orgasm, with more men than women reporting they always have an orgasm. Men are also more likely to report their partners also always had orgasms.
Summary of events in a typical humoral immune response.
Night Attack on the Sanjo Palace (detail), from the Scrolls of Events of the Heiji Period.
Calipers being used to measure body fat on the triceps of a patient.
A goniometer is used to measure range of motion of the patient’s arm.
To measure engine oil pressure, remove the oil pressure sending (sender) unit usually located near ...
A Breathalyzer is used to measure a person's blood alcohol concentration (BAC)