Consider the following examples of two different types of statistical investigations. Example 1 Radio rating services sometimes collect data on listenership by asking participants to record the date, time, and station each time they listen to the radio.
Popular types of invisible braces include ceramic brackets, inside braces and clear aligners. Ceramic braces are just like metal braces, except that they use tooth-colored brackets (and sometimes tooth-colored wires) rather than metal to straighten teeth.
Dental braces are devices used to align, straighten and correctly position teeth by exerting steady pressure over a period of time, usually one to three years. Braces typically consist of brackets (bonded to the teeth), bands and wires.