Answer:
The answer is a double-blind study.
Explanation:
A double-blind study is a research method in which neither the participants or the researchers are aware about which group is receiving the treatment. This is done in order to avoid biases such as the placebo effect, as well as preventing accidental cues given by the researchers.
The greatest advantage of this approach is its high validity.
Answer:
Could you give more info?
Explanation:
D,photographs do not give an accurate picture
Answer: MAPE
Explanation: MAPE (Mean Absolute Percentage Error (MAPE) is a statistical measure of how accurate a forecast system is. It measures the size of the error in percentage terms.This scale sensitivity renders the MAPE close to worthless as an error measure for low-volume data where as MAD (Mean Absolute Deviation) measures the size of the error in units. Hence MAPE would be a more meaningful measure of forecast accuracy.