What is the Mean Absolute Deviation for Daily High Temperatures in St. Louis?

AI Thread Summary
The discussion centers on calculating the Mean Absolute Deviation (MAD) for daily high temperatures in St. Louis, which were recorded as 92, 91, 94, 95, 96, 88, and 90. The correct MAD based on a 2-day moving average is confirmed to be 3.20. Participants initially struggled with understanding the 2-day moving average concept but eventually received clarification. The step-by-step breakdown includes calculating the 2-day averages and the absolute errors, leading to the final MAD result. The conversation highlights the importance of grasping the moving average for accurate forecasting.
smashedpumpki
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I understand MAD, but I cannot figure out this question. Here's the information.

Daily high temperatures in St. Louis for the last week were as follows: 92, 91, 94, 95, 96, 88,90.
The mean absolute deviation based on a 2-day moving average = 3.20

How in the world is it 3.20? I've tried 100's of combinations to try to repeat this answer, but I can't do it. I'm 100% sure this is the correct answer. Can anyone please show me a step by step walk through on this problem? I've spent all day on this... I know it has to be simple.
 
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I'm getting 4.2 :mad:

How you did the problem?
 
I got it! I finally got some help that really explained what 2-day moving average means. This is a forecasting problem.

Numbers - 92, 91, 94, 95, 96, 88,90
2-Day Averages - 91.5, 92.5, 94.5, 95.5, 92
Absolute Error - 2.5, 2.5, 1.5, 7.5, 2
MAD = 3.2
 
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