# **Appendix: Data and methodological issues**

This study relies on a relatively small number of assumptions and simplifications to work around the absence of data in some areas. It also constitutes only a first step towards a more comprehensive tool to integrate land use changes as a policy relevant option to achieve thicker and more efficient labor markets. As such some methodological choices and data related issues deserve to be discussed.

## **Data choices:**

- <u>Imperfect data about number and location of jobs: the amount and location of formal economic</u> opportunities are inferred from a detailed land use map, associating them with the quantity of land used for industrial, commercial and public utility purposes. This is suboptimal as it does not provide exact information about job numbers and location. The correlation between land uses and economic opportunities is loose: it is indeed uneasy to associate number of square meters used for industrial purposes with a number of industrial jobs. The same applies for commercial activities etc... But even accepting the bold idea that job numbers are proportional to number of square meters, the land use map used in this study does not provide information about building heights, only land plot size. Therefore, one storey buildings are considered in the same way as six storey buildings. The strong assumptions that we make are the unfortunate consequence of the lack of data. We will however pursue efforts aimed at identifying or producing more accurate sources for counting and locating formal jobs in the urban area of Nairobi County. As a follow up to this study the team will apply the same methodology to assess accessibilities and their potential enhancements through land use occupation changes in Kampala, Uganda. In Kampala, detailed registries on employment quantities and locations exist and will increase the accuracy of our conclusions.

- <u>Other public or collective transportation options besides matatus:</u> In parallel to the informal minibus system – matatus – discussed in this paper, there exists both a formal bus system and railway commuter service in Nairobi. Buses operate on roughly 67 routes and carry a smaller percentage of the population than matatus (350,000-400,000 passengers per day). With competing companies, bus service is not provided in an efficient manner, maintenance suffers, and profitability margins are low. Contributing to the inefficiencies of the public transport system is the fact that many of these buses travel along the same routes as the matatus, competing for limited space in the already congested CBD (Consulting Engineering Services (India) Private Limited 2010). Also complicating matters is that routes have been optimized to maximize efficiency for the operator and not coordinated to an efficient level in maximizing passenger comfort or convenience. Nairobi was founded as a railway town, and its rail infrastructure remains well connected to the city center. Rift Valley Railways (RVR) offers twice daily service on five commuter rail routes in the Nairobi metropolitan region, averaging 2,300 to 6,900 passengers per route. While commuter rail is an economical mode of public transport, at present it serves only a tiny fraction of the daily commuting needs of the Nairobi general public. The most commonly cited reasons by Nairobians for not utilizing the system are concerns with safety and comfort, along with protracted travel times and difficult access to stations (Consulting Engineering Services (India) Private Limited 2010). Both these transport modes carry only a fraction of daily commuters in Nairobi so their initial omission is not too problematic; in the future however the team will look to integrate these networks into the analysis.

- <u>Monetary costs of the various transportation options: The analysis conducted in this study only</u> considers transport times in determining accessibilities. A more complete analysis would reason in

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