Exam 3 QMB3250 UF questions with correct answers

Exam 3 QMB3250 UF questions with
correct answers

For Simple moving average, longer periods are _________ than shorter periods.
o o o o o o o o o o




Smoother or less smooth - ANSWER: ➡ Smoother o o o o o oo o




Creates a new time series from the original data by averaging adjacent values.
o o o o o o o o o o o o




helps illuminate how the data is varying over time.
o o o o o o o o




Affected by outliers and peaks. o o o o




Doesn't work well when there are strong seasonal, trend or cyclical components. - ANSWER:
o o o o o o o o o o o o o o




➡ Simple Moving Average
o o o o




values that are closest to the estimated value get the most weight in the moving average and
o o o o o o o o o o o o o o o o




values that are farther away get less.
o o o o o o o




adjust weight between recent and historic data. - ANSWER: ➡ Simple exponential smoothing
o o o o o o o o oo o o o




A smaller a (alpha) would be __________________.
o o o o o o




Smoother or more flat or less smooth - ANSWER: ➡ Smoother
o o o o o o o o oo o




Time series where we add in columns containing lags.
o o o o o o o o




Good for quarterly lag. - ANSWER: ➡ Autoregressive models
o o o o o oo o o




We can cautiously predict a little further away from the data. Better at fitting series that have
o o o o o o o o o o o o o o o o




trend, cyclical, and seasonal components.
o o o o o




Linear
- Additive: SLR
o o o




- Exponential: SLR but log(y)
o o o o

, Quarters: Add indicator variables - ANSWER: ➡ Multiple Regression Models
o o o o o oo o o o




the best prediction is the most recent point. Time series.
o o o o o o o o o




Sometimes described as white noise. - ANSWER: ➡ Random walk o o o o o o oo o o




Allow us to compare two or more means.
o o o o o o o




Ho: M1 = M2 = Mk (No difference in treatments)
o o o o o o o o o




Ha: At least one population mean is different from the rest. - ANSWER: ➡ One way ANOVA
o o o o o o o o o o o o oo o o o




an extra variable added to help predict this cyclical trend. - ANSWER: ➡ exogenous variable
o o o o o o o o o o o oo o o




estimates how much the means vary. o o o o o




gets bigger by adding another group. - ANSWER: ➡ sum of squares treatment
o o o o o o o oo o o o o




estimates how much variation there is within each group. - ANSWER: ➡ sums of squares error
o o o o o o o o o o oo o o o o




The confidence level is found by using 1 - a/j
o o o o o o o o o




where j is the number of comparisons. - ANSWER: ➡ Bonferroni method
o o o o o o o o oo o o




two factors with multiple levels.
o o o o




We look at effects using an interaction plot.
o o o o o o o




Interaction present -> multiple comparisons. o o o o




No interaction present-> look at main effects. - ANSWER: ➡ two way ANOVA
o o o o o o o o oo o o o




when the effects of one factor are NOT similar across all levels of the other factor. - ANSWER: ➡
o o o o o o o o o o o o o o o o o oo




interaction
o