QMB 3200 FINAL UCF questions with
answers
Autocorrelation - ** VERIFIED ANSWERS **✔✔Correlation in the errors that arises when the error
terms at successive points in time are related.
Durbin-Watson test - ** VERIFIED ANSWERS **✔✔A test to determine whether first-order
autocorrelation is present.
General linear model - ** VERIFIED ANSWERS **✔✔A model of the form y=β0+β1z1+β2z2+⋯
+βpzp+ε, where each of the independent variables zj(j=1,2,...,p) is a function of x1,x2,...,xk, the
variables for which data have been collected.
interaction - ** VERIFIED ANSWERS **✔✔The effect produced when the levels of one factor
interact with the levels of another factor in influencing the response variable.
The effect of two independent variables acting together.
variable selection procedures - ** VERIFIED ANSWERS **✔✔Methods for selecting a subset of the
independent variables for a regression model.
Time series - ** VERIFIED ANSWERS **✔✔A sequence of observations on a variable measured at
successive points in time or over successive periods of time.
Mean Squared Error (MSE) - ** VERIFIED ANSWERS **✔✔The average of the sum of squared
forecast errors.
,Time series plot - ** VERIFIED ANSWERS **✔✔A graphical presentation of the relationship
between time and the time series variable. Time is shown on the horizontal axis and the time series
values are shown on the vertical axis.
horizontal pattern - ** VERIFIED ANSWERS **✔✔A horizontal pattern exists when the data
fluctuate around a constant mean.
moving average - ** VERIFIED ANSWERS **✔✔A forecasting method that uses the average of the
most recent k data values in the time series as the forecast for the next period.
stationary time series - ** VERIFIED ANSWERS **✔✔A time series whose statistical properties are
independent of time. For a stationary time series the process generating the data has a constant
mean and the variability of the time series is constant over time.
trend pattern - ** VERIFIED ANSWERS **✔✔A trend pattern exists if the time series plot shows
gradual shifts or movements to relatively higher or lower values over a longer period of time.
smoothing constant - ** VERIFIED ANSWERS **✔✔A parameter of the exponential smoothing
model that provides the weight given to the most recent time series value in the calculation of the
forecast value.
seasonal pattern - ** VERIFIED ANSWERS **✔✔A seasonal pattern exists if the time series plot
exhibits a repeating pattern over successive periods. The successive periods are often one-year
intervals, which is where the name seasonal pattern comes from.
cyclical pattern - ** VERIFIED ANSWERS **✔✔A cyclical pattern exists if the time series plot shows
an alternating sequence of points below and above the trend line lasting more than one year.
mean absolute error - ** VERIFIED ANSWERS **✔✔The average of the absolute values of the
forecast errors.
When autocorrelation is present... - ** VERIFIED ANSWERS **✔✔the error terms are not
independent.
, The Durbin-Watson test statistic ranges in value from - ** VERIFIED ANSWERS **✔✔zero to four
If successive values of the residuals are close together (positive autocorrelation) - ** VERIFIED
ANSWERS **✔✔the value of the Durbin-Watson test statistic will be small.
If successive values of the residuals are far apart (negative autocorrelation) - ** VERIFIED
ANSWERS **✔✔the value of the Durbin-Watson statistic will be large.
Null Hypothesis (Ho) - ** VERIFIED ANSWERS **✔✔The hypothesis tentatively assumed true in
the hypothesis testing procedure
Two-tailed test - ** VERIFIED ANSWERS **✔✔A hypothesis test in which rejection of the null
hypothesis occurs for values of the test statistic in either tail of its sampling distribution.
Alternative Hypothesis (Ha) - ** VERIFIED ANSWERS **✔✔The hypothesis concluded to be true if
the null hypothesis is rejected
P-Value - ** VERIFIED ANSWERS **✔✔A probability that provides a measure of the evidence
against the null hypothesis given by the sample
Type 1 error - ** VERIFIED ANSWERS **✔✔The error of rejecting Ho when it is true
Type 2 error - ** VERIFIED ANSWERS **✔✔The error of accepting H0 when it is false
Level of significance (alpha level) - ** VERIFIED ANSWERS **✔✔The probability of making a Type
1 error when the hypothesis is true as an equality
Critical Value - ** VERIFIED ANSWERS **✔✔A value that is compared with the test statistic that
helps determine whether Ho should be rejected.
answers
Autocorrelation - ** VERIFIED ANSWERS **✔✔Correlation in the errors that arises when the error
terms at successive points in time are related.
Durbin-Watson test - ** VERIFIED ANSWERS **✔✔A test to determine whether first-order
autocorrelation is present.
General linear model - ** VERIFIED ANSWERS **✔✔A model of the form y=β0+β1z1+β2z2+⋯
+βpzp+ε, where each of the independent variables zj(j=1,2,...,p) is a function of x1,x2,...,xk, the
variables for which data have been collected.
interaction - ** VERIFIED ANSWERS **✔✔The effect produced when the levels of one factor
interact with the levels of another factor in influencing the response variable.
The effect of two independent variables acting together.
variable selection procedures - ** VERIFIED ANSWERS **✔✔Methods for selecting a subset of the
independent variables for a regression model.
Time series - ** VERIFIED ANSWERS **✔✔A sequence of observations on a variable measured at
successive points in time or over successive periods of time.
Mean Squared Error (MSE) - ** VERIFIED ANSWERS **✔✔The average of the sum of squared
forecast errors.
,Time series plot - ** VERIFIED ANSWERS **✔✔A graphical presentation of the relationship
between time and the time series variable. Time is shown on the horizontal axis and the time series
values are shown on the vertical axis.
horizontal pattern - ** VERIFIED ANSWERS **✔✔A horizontal pattern exists when the data
fluctuate around a constant mean.
moving average - ** VERIFIED ANSWERS **✔✔A forecasting method that uses the average of the
most recent k data values in the time series as the forecast for the next period.
stationary time series - ** VERIFIED ANSWERS **✔✔A time series whose statistical properties are
independent of time. For a stationary time series the process generating the data has a constant
mean and the variability of the time series is constant over time.
trend pattern - ** VERIFIED ANSWERS **✔✔A trend pattern exists if the time series plot shows
gradual shifts or movements to relatively higher or lower values over a longer period of time.
smoothing constant - ** VERIFIED ANSWERS **✔✔A parameter of the exponential smoothing
model that provides the weight given to the most recent time series value in the calculation of the
forecast value.
seasonal pattern - ** VERIFIED ANSWERS **✔✔A seasonal pattern exists if the time series plot
exhibits a repeating pattern over successive periods. The successive periods are often one-year
intervals, which is where the name seasonal pattern comes from.
cyclical pattern - ** VERIFIED ANSWERS **✔✔A cyclical pattern exists if the time series plot shows
an alternating sequence of points below and above the trend line lasting more than one year.
mean absolute error - ** VERIFIED ANSWERS **✔✔The average of the absolute values of the
forecast errors.
When autocorrelation is present... - ** VERIFIED ANSWERS **✔✔the error terms are not
independent.
, The Durbin-Watson test statistic ranges in value from - ** VERIFIED ANSWERS **✔✔zero to four
If successive values of the residuals are close together (positive autocorrelation) - ** VERIFIED
ANSWERS **✔✔the value of the Durbin-Watson test statistic will be small.
If successive values of the residuals are far apart (negative autocorrelation) - ** VERIFIED
ANSWERS **✔✔the value of the Durbin-Watson statistic will be large.
Null Hypothesis (Ho) - ** VERIFIED ANSWERS **✔✔The hypothesis tentatively assumed true in
the hypothesis testing procedure
Two-tailed test - ** VERIFIED ANSWERS **✔✔A hypothesis test in which rejection of the null
hypothesis occurs for values of the test statistic in either tail of its sampling distribution.
Alternative Hypothesis (Ha) - ** VERIFIED ANSWERS **✔✔The hypothesis concluded to be true if
the null hypothesis is rejected
P-Value - ** VERIFIED ANSWERS **✔✔A probability that provides a measure of the evidence
against the null hypothesis given by the sample
Type 1 error - ** VERIFIED ANSWERS **✔✔The error of rejecting Ho when it is true
Type 2 error - ** VERIFIED ANSWERS **✔✔The error of accepting H0 when it is false
Level of significance (alpha level) - ** VERIFIED ANSWERS **✔✔The probability of making a Type
1 error when the hypothesis is true as an equality
Critical Value - ** VERIFIED ANSWERS **✔✔A value that is compared with the test statistic that
helps determine whether Ho should be rejected.
