If we use the mean as a model, what does the variance represent?
Question 8 options:
|
|||
|
|||
|
|||
|
The variance measures how far each number in the set is from the mean.
Variance is calculated by taking the differences between each number in the set and the mean, squaring the differences and dividing the sum of the squares by the number of values in the set.
Therefore correct option is
c) |
The squared total error between the model and the observed data. |
If we use the mean as a model, what does the variance represent? Question 8 options:...
Before implementing a forecasting model is it important to Question 8 options: A. Utilize an alternative source of data to generate the actual forecasts. B. Make sure that you have found the model with the largest MAE. C. Rerun the model on the entire series (training+validation) in order to utilize the most recent data in generating your forecasts D. Rerun the model using the validation period only in order to avoid using ‘old’ data. Question 9 (1 point) Using the...
2. Use the data in hpricel.wfl uploaded on Moodle for this exercise. We assume that all assump- tions of the Classical Linear Model are satisfied for the model used in this question. (a) Estimate the model and report the results in the usual form, including the standard error of the regression. Obtain the predicted price when we plug in lotsize - 10, 000, sqrft - 2,300, and bdrms- 4; round this price to the nearest dollar. (b) Run a regression...
2 pts Question 4 In the classical regression model we maximize the sum of the squared errors. O True False 2 pts D Question 5 The terms coefficients of determination and R-square are synonyms, measuring how well a regression model fits the data. O True False 2 pts Question 6 Student's t-statistic is calculated as the ratio of an estimated coefficient divided by its standard error. True False
Q54) [1 Point] Which of the following learning curves represent a good linear regression model? Validation Error Training Error Error Error Error Training set size Training set size Model-1 Training set size Model-3 Model-2 A) Model-1 B) Model-2 C) Model-3 Q55) [1 Point] Maximal margin classifiers are sensitive to outliers in training data. A) True B) False Q56) [1 Point] Soft margin classifiers allows for misclassification in training data. A) True B) False Q57) [1 Point] Which of the following...
D Question 6 5 pts What model would you use in a hypothesis test the difference between two means? O t O Chi square OF D l Question 7 5 pts Suppose a glass factor samples 2000 glasses. There are flaws in 75 of them. Find a 95% confidence interval for the true proportion of flaws. O (033,.041) O (0,.0375) O (0356.0393) O (029,.046) Question 8 If the estimated mean from sample is 10, then O is equivalent to the...
1. When do we use an independent groups t-test? a. b. c. d. When we are comparing means from one sample that has been measured twice. When we are comparing means from two different samples. When we are comparing a sample mean to a population mean. When we are comparing two population means. 2. Which of the following is true regarding the use of t-tests for true experiments versus quasi-experimental designs? a. b. We use the same t-test whether it...
Suppose we want to estimate a parameter θ of a certain distribution and we have the following independent point estimates N(0+0.1,0.01) N(0, 0.04) B2 ~ a) What are the mean square errors for these point estimates? (4pts) b) Find a point estimate with mean square error less than or equal to 0.01. (2pts) c) Only use ël and Ộ2, find the unbiased estimator with the smallest variance possible. What is that estimator? What is the smallest variance? (6pts) Suppose we...
Given forecast errors of 8, 10, and 9, what is the mean absolute deviation? O A. 2/3 B. 1/3 C.:a. D. O QUESTION 5 Given forecast errors of 3, 6, and 9, what is the mean square error? A. 5 B. 6 c.7 D. 8 We were unable to transcribe this imageTime-series data may exhibit which of the following behaviors? O A. Trend B. Seasonality C. Cycles D. All of the above QUESTION 9 In business, forecasts are the basis...
8) The following numbers represent quiz scores for 15 students. What is the mean score? (Enter your answer rounded to the tenths place, e.g. enter 8.3 instead of 8. Do not include units.) 4,5,5,6,7,7,7,8,8,8,9,9,9,9,10 Answer: For the distribution of quiz scores above, what is the median quiz score? Answer: 9) 10) Which of the following statements is always true? a). Half of the data is above the mean and half of the data is below the mean b). There are...
6.72 Let Y =X+N where X and N are independent Gaussian random variables with different variance and N is zero mean. (a) Plot the correlation coefficient between the “observed signal” Y and the “desired signal” X as a funtion of the signal-to-noise ratio (b) Find the minimum mean square error estimator for X given Y (c)Find the MAP and ML estimators for X given Y (d) Compare the mean square error of the estimators in parts a, b, and c.