In Phuong's proofreading experiment, what are the independent and dependent variables?

In the context of Phuong's proofreading experiment, the independent variable refers to the factor that is manipulated or varied by the researcher to observe its effects, while the dependent variable is the outcome that is measured in response to the manipulation.

In this case, the type of proofreading represents the different conditions or methods that Phuong is testing—these could include various proofreading strategies or techniques. The number of errors is the measurable outcome, reflecting how many mistakes were identified during proofreading under each type of proofreading condition.

By analyzing the number of errors made in relation to the type of proofreading, the researcher can determine if different methods significantly affect proofreading accuracy. The other options do not align as neatly with the definitions of independent and dependent variables in the context of a proofreading experiment. For instance, average reading time and reading speed might be pertinent to reading comprehension but do not directly evaluate the effectiveness of the proofreading methods themselves.