Case 1: Probabilities cannot add up to a number greater (or less) than 1. This would mean there is greater than a 100% chance of something happening which just doesn't make sense. 0.4 + 0.4 + 0.3 = 1,1
Case 2: You cannot have a negative probability. That is claiming that there is a -10% chance of an event happening, there is at the very least a 0%. Despite them "adding" up to 1, the negative probability makes no sense.
Hope I helped!
Answer:
A negative correlation means that there is an inverse relationship between two variables - when one variable decreases, the other increases. The vice versa is a negative correlation too, in which one variable increases and the other decreases.
Step-by-step explanation:
Answer: A 2,2
Step-by-step explanation: 1 - 1 something
For a smoothing constant of 0.2
Time period – 1 2 3 4 5 6 7 8 9 10
Actual value – 46 55 39 42 63 54 55 61 52
Forecast – 58 55.6 55.48 52.18 50.15 52.72 52.97 53.38 54.90
Forecast error - -12 -.6 -16.48 – 10.12 12.85 1.28 2.03 7.62 -2.9
The mean square error is 84.12
The mean forecast for period 11 is 54.38
For a smoothing constant of 0.8
Time period – 1 2 3 4 5 6 7 8 9 10
Actual value – 46 55 39 42 63 54 55 61 52
Forecast – 58 48.40 53.68 41.94 41.99 58.80 54.96 54.99 59.80
Forecast error - -12 6.60 -14.68 0.06 21.01 -4.80 0.04 6.01 -7.80The mean square error is 107.17
The mean forecast for period 11 is 53.56
Based on the MSE, smoothing constant of .2 offers a better model since the mean forecast is much better compared to the 53.56 of the smoothing constant of 0.8.