William is participating along with a group of adolescents trying to lose weight. one of his assignments is to keep a diary of his food intake and the times that he eats daily. this can be considered an example of what type of research

Research can be defined as a systematic and scientific collection, analysis, and interpretation of data. Research can be classified in several different ways based on its purpose, methodology, time frame, and other attributes.

A broad classification divides research into quantitative and qualitative research. Quantitative research is commonly identified by its use of numbers, and it is often concerned with measurements and calculations. On the other hand, qualitative research is more descriptive, and it focuses on the "qualities" of the object of study. If we use this classification, a food diary would contain elements of both categories. There will be quantitative qualities in terms of the number of times William eats or the portion size, while there will be qualitative elements when we need to describe the food that was consumed.

On the other hand, research can also be divided by its nature into analytical and descriptive. Analytical research is when the researcher uses material that already exists to make a critical study of his material. Descriptive research focuses on recording things as they are at present, with no control over other variables. Under this classification, the food diary would be considered an example of descriptive research.