Answer to Question 1
By assigning participants to groups on the basis of the flip of a coin, numbers drawn from a hat, or a table of random numbers, the chance is increased that characteristics other than the independent variable will be equally distributed across treatment groups.
Answer to Question 2
The rate and expression of childhood symptoms and disorders often vary in relation to demographic and situational factors, such as socioeconomic status (SES) (e.g., the social, economic, and physical environment in which the child lives as reflected in measures such as family income, education, or occupation); parents' marital status; and the child's age, gender, and cultural background, to name but a few. Consequently, these variables must be assessed and controlled in most studies.
Polyploidy has been an important factor in the evolution of plants.
In 1891 William Dean Howells championed the poetry of Emily Dickinson: “This poetry is as characteri
Normal combustion is a smooth, controlled burning of the air–fuel mixture.
Important Concepts in Clinical Massage Therapy
Student Perspective of Research
Research Methods