The time-of-day choice is another optional choice level following the mode choice. Per demand segment, the total demand is distributed in the time dimension according to time interval-specific utility matrices. This results in a demand matrix with a demand time profile that you can immediately use in PuT assignments or in dynamic PrT assignments (Fundamentals: Time-of-day choice).
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Note: Demand strata are not required for this procedure. Thus, you can execute it independently from other steps of the Standard 4-step model. |
1. On the toolbar, click the 
Open 'Procedure sequence' window button.
The Procedure sequence window opens.
2. To the procedure sequence, at the position of your choice, add the Time-of-day choice procedure of the Demand model category (Setting up and starting the procedure sequence).
3. In the row of the newly inserted procedure, in the Reference object(s) column, click the button.
The Select matrix window opens.
4. Click the matrix whose values you want to use for demand calculation. Here, two methods are provided (Selecting matrices).
| Element | Description |
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Select matrix directly |
From the list of all matrices, select the desired matrix by its number. |
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Select matrix by properties |
Select a matrix by certain attributes and their values. |
5. Select the desired demand matrix.
6. Confirm with OK.
The selected matrix is listed in the Reference object(s) column.
7. Make sure the procedure inserted is marked. In the Operations section, click the Edit button.
The Time-of-day choice parameters window opens.
8. Make the desired changes.
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Element |
Description |
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Set all interval values to zero prior to calculation |
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Time choice model |
Via this button you can select a utility function which serves for transformation of the values resulting from the combination (Setting utility function parameters for time-of-day choice). |
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Selection of a standard time series |
Via the list box, you can select a standard time series. The demand matrix selected as reference object will be distributed to the time intervals of the selected standard time series (Managing time series).
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Time interval |
Via the list box, you can select the desired time interval of the standard time series (Creating time intervals for standard time series). |
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Result demand matrix |
Reference to the demand matrix being allocated to the particular time interval of the standard time series (Creating time intervals for standard time series). Note The allocated result matrix is only displayed for time series of matrix numbers. |
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Utility U |
Linear combination of matrices, attribute vectors and/or constants per time interval (Combining matrices and attribute vectors in the Matrix editor window) Note The result of the combination is interpreted as utility matrix. |
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Create |
Insert row in list |
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Delete |
Delete marked row from list |
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1st column |
If the list contains more than one entry, the + sign indicates that the entries are added row by row. |
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Matrix / Attribute / Constant |
This button opens the Select operand window, which allows you to select a Visum skim matrix, zone attribute or constant. You can use a function to convert the values of the object selected (Transformation column). You can further multiply them by a factor (Coefficient column). |
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Transformation |
In the list box, click the function of your choice to convert the values selected in the Matrix / Attribute / Constant column (Editing matrix values). |
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Coefficient |
Factor by which the values are multiplied one element at a time |
If this option has been selected, all values of the time intervals allocated to the standard time series are set to 0 prior to the calculation.
If this option has not been selected, the following values are added to the weight of the selected time interval 9. Confirm with OK.
10. Execute the procedure (Executing procedures in the procedure sequence).
The time-of-day choice is calculated and the results are saved per time interval to the result matrix (time series of matrix numbers) or to the Weight column of the Edit time series window (Time series by percentage) (Creating time intervals for standard time series).
Setting utility function parameters for time-of-day choice
1. Make sure that the Time-of-day choice parameters window is open (Calculating Time-of-day choice).
2. Make sure that the desired demand matrix has been selected.
3. Click the Time choice model button.
The Choice model for <Matrix name> window opens.
4. Select the Settings tab.
5. Make the desired changes.
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Element |
Description |
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Function type |
Utility function type for calculation of time-of-day choice |
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Parameters |
a, b, c Estimated parameter values for the utility function. The parameters can take negative values. Notes The Function graph tab shows the curve progression of the utility function due to current parameter settings. If the initial matrix contained impedance data such as distances or travel times, negative exponents need to be entered for the utility function. |
6. Select the Function graph tab.
The curve progression of the utility function is shown with the currently set parameters a, b, and c.
7. In the Range section, you may edit the scaling of the x axis and the y axis, if applicable.
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Element |
Description |
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X Min |
Minimum value for x-axis (negative values allowed) |
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X Max |
Maximum value for x-axis |
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Y Min |
Minimum value for y-axis (negative values allowed) |
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Y Max |
Maximum value for y-axis |
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Apply |
Click this button to use the entered values for the graph and to update the curve progression. |
8. If required, in the Parameters section, edit the parameters a, b, and c of the utility function.
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Tip: Alternatively, you can edit the parameters in the Options tab. |
9. Click the Apply button.
The entered parameter values are applied to the graph and will thus update the curve progression.
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Tip: To reset the utility function parameter values and the curve progression to standard values, click the Reset button. |
10. Confirm with OK.
The changes are applied.
