For each tour, the Metrolina model predicts the choice of forward and return time periods with the choices being Peak (PK) or Off-peak (OP). Therefore, every tour falls under one of four categories depending on the forward and return period, namely PK_PK, PK_OP, OP_PK, OP_OP. The previous version of the model reverts to a trip-based approach after destination choice. PK and OP matrices were generated by purpose on which the mode choice models were evaluated. A TOD model then subsequently splits the PK and OP mode choice output matrices by using PA/AP factors to generate subperiod (AM, MD, PM and NT) matrices.

The updated Metrolina model deviates slightly from this approach. Like in the previous model, the forward and return period (PK/OP) is predicted for each tour. However, the mode choice is also tour-based, and the time-of-day model is applied just before the creation of the OD matrices. Therefore, there is a need to generate 4 sets of matrices (AM, MD, PM and NT) from the tour level output.

This is done by analyzing the survey to apportion the appropriate combination of PK_PK, PK_OP, OP_PK and OP_OP tours into sub-periods. For example, the PK_PK combination has three possibilities (AM_AM, AM_PM and PM_PM). The survey was used to obtain percentages of tours in each subcategory by purpose. These are directly applied in the model.

The tables containing these factors are shown below.

Peak to Peak factors

Tour Distribution
Work School University Shop Other AtWork
AM_AM 21,450 43,915 1,073 12,444 162,307 4,376
AM_PM 245,819 117,975 11,933 14,554 103,305 919
PM_PM 5,490 3,523 139 47,762 144,099 3,304
Total 272,759 165,413 13,145 74,759 409,711 8,599
Percentage Distribution
AM_AM 7.9% 26.5% 8.2% 16.6% 39.6% 50.9%
AM_PM 90.1% 71.3% 90.8% 19.5% 25.2% 10.7%
PM_PM 2.0% 2.1% 1.1% 63.9% 35.2% 38.4%

Peak to Off-Peak factors

Tour Distribution
Work School University Shop Other AtWork
AM_MD 50,499 58,609 10,349 43,509 135,633 2,785
AM_NT 99,474 13,508 5,368 13,297 39,825 36
PM_NT 19,378 4,182 4,959 52,959 193,032 564
Total 169,350 76,299 20,675 109,765 368,490 3,386
Percentage Distribution
AM_MD 29.8% 76.58% 50.1% 39.6% 36.8% 82.3%
AM_NT 58.7% 17.7% 26.0% 12.1% 10.8% 1.1%
PM_NT 11.4% 5.5% 24.0% 48.2% 52.4% 16.7%

Off Peak to Peak factors

Tour Distribution
Work School University Shop Other AtWork
MD_PM 32,206 3,243 1,002 62,524 155,120 5,407
NT_AM 7,567 1,866 568 2,653 15,894 72
NT_PM 76,713 13,621 133 5,241 28,077 0
Total 116,486 18,730 1,703 70,417 199,091 5,480
Percentage Distribution
MD_PM 27.6% 17.3% 58.8% 88.8% 77.9% 98.7%
NT_AM 6.5% 10.0% 33.3% 3.8% 8.0% 1.3%
NT_PM 65.9% 72.7% 7.8% 7.4% 14.1% 0.0%

Off Peak to Off Peak factors

Tour Distribution
Work School University Shop Other AtWork
MD_MD 11,955 6,686 2,167 156,742 310,301 57,697
MD_NT 45,843 788 2,958 17,405 53,755 32
NT_MD 22,337 4,046 425 751 10,608 34
NT_NT 53,916 3,380 4,681 48,629 187,114 1,950
Total 134,052 14,900 10,232 223,527 561,779 59,714
Percentage Distribution
MD_MD 8.9% 44.9% 21.2% 70.1% 55.2% 96.6%
MD_NT 34.2% 5.3% 28.9% 7.8% 9.6% 0.1%
NT_MD 16.7% 27.2% 4.2% 0.3% 1.9% 0.1%
NT_NT 40.2% 22.7% 45.7% 21.8% 33.3% 3.3%