Summary of the work completed so far on Zanzibar

In June, we signed the contract for the work on Tanzania Resilience Academy. Shortly after that, on June 16, we visited Zanzibar where we met the Resilience Academy team, reviewed the venue and equipment, discussed the plans for the training, and organized logistics for our team.

In July, we prepared a Curriculum for the Industrial Training and wrote the Inception Report. We again visited Zanzibar on July 18 to review the documents with the team on Zanzibar and worked out the logistics for the training.

After that, the team took a short summer break for two weeks but early by August, we were back in the office. We purchased all the necessary equipment and Justus and I relocated to Zanzibar for at least a couple of months.

The Industrial Training started on August 20. Approximately 50 students were introduced to mapping theory and best practices during the first week of training, and on Thursday, August 22, we organized a stakeholder meeting to determine the mapping themes and the scope of the mapping exercise.

After the initial week of theory, the students spent the last three weeks in the field collecting data and updating OpenStreetMap of the Zanzibar Urban West. By the end of week four, we will have mapped (collect information on basic public amenities) almost 40 shehias (wards) in the city.

The work continues…

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Zanzibar Resilience Academy

Since 2017, we spent many months on Zanzibar working with the government and other stakeholders on data collection activities. The main focus of these activities was to utilize the rectified drone imagery provided by the Zanzibar Mapping Initiative and generate datasets critical to disaster risk management.

Between May 2017 and March 2018, the first phase of the project called Digitizing the Outputs of the Zanzibar Mapping Initiative was implemented. The main landmarks of this phase include establishing a digitization laboratory at the Commission for Lands (COLA); determining digitization and quality control standards; training 30 COLA staff and State University students in digitization; altogether, approximately 220,000 buildings were digitized, reviewed and cleaned with building reference numbers assigned to each building.

Then, between July 2018 and February 2019, the second phase called Open Cities Africa was carried out. This project built on the first by adding 180,000 buildings to the map and implementing a GPS and household survey in the Zanzibar City’s center. Finally, several maps were produced, including an interactive map on urban resilience.

In mid-2019, we are building on these two initiatives through the Resilience Academy’s Industrial Training. This project is a part of the larger Tanzania Resilience Academy Initiative that targets four Universities across Tanzania. The  Zanzibar program will teach 50 students from the State University all the nitty-gritty of community mapping, from project design, budget allocation, equipment set-up, to carrying out independent mapping of communities based on the stakeholders’ needs.

Specifically, this assignment will:

  1. Provide a good working environment for emerging data and technological communities on Zanzibar, with the focus on University students;

  2. Design and implement mapping of Zanzibar City and create an openly licensed dataset;

  3. Ensure all data collected is collected to an agreed quality standard;

  4. Build a cadre of students to implement community mapping; and

  5. Produce maps and datasets.

The Resilience Academy training on Zanzibar began on the 20th of August 2019 and will continue for the next 8 weeks, so many more blog posts coming soon.

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User Experience Testing of Mobile Applications for Cadastral Surveys

Following our previous blog post titled Technical Testing of Mobile Applications for Cadastral Surveys, we continue our look back at the work we did a while ago on evaluating mobile tools/apps aimed at cadastral surveys and land/property mapping. In this blog post, we explain the tool we developed for user experience testing of mobile applications.

The user experience testing of application touched on evaluating the experience of users while operating selected mobile applications during fieldwork. Indicators such as accessibility, flow, functionality, information architecture, consistency, and satisfaction were developed during the user experience workshop in Nairobi and then tested in the field, in Taita Hills.

Below is a breakdown of the tool for testing the user experience criteria and rationale:

1. Accessibility: Is it clear where to go to in the application to achieve different tasks? Is it obvious, which buttons to press and which not to press?

The application should be accessible through clear language and functionality so that the user can intuitively accomplish relevant tasks without confusion.

2. Flow: Is the path from start to finishing clear?

The process of accomplishing a task should be as simple as possible from start to finish. The user should be able to know at what step of the process he/she is, what the next step is, and how to track back if necessary.

3. Functionality: Does the application load quickly? Are there any dead links or ‘glitches’?

Functionality touches mainly on the technical features of mobile phones and its interaction with the application. In developing countries, the majority of the people own medium- to low-end smartphones and, as such, the mobile application should be built in a way that these mobile phones can sustain it.

4. Information Architecture: Does the application have good navigation? Are the icons understandable? Is labeling consistent across the application?

The application should have clear and simple navigation, good visual cues, and well-considered iconography that aids the user through different tasks.

5. Consistency: Is the application consistent throughout in order for the user to perform additional tasks without problems?

The application should have a common convention that requires a short learning curve in case new tasks are necessary. Multiple conventions can be disorienting and frustrating for a user with limited technical capacity.

6. Satisfaction: Is it satisfactory to use the applications? Did the application sufficiently fulfill the intended task?

Was the work accomplished with minimum user experience friction and in a satisfactory manner?

These are the user-experience specifications we developed and tested in the field. The next blog post will look at the field testing itself.

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Technical Testing of Mobile Applications for Cadastral Surveys

Following our previous blog post titled Introduction to User Experience Testing of Mobile Applications for Cadastral Surveys, we continue our look back at the work we did a while ago on evaluating mobile tools/apps aimed at cadastral surveys and land/property mapping. In this blog post, we explain the tool we developed for technical testing of mobile applications.

Through user experience workshops, we designed an evaluation tool that can be used to scrutinize mobile applications against the highest professional standards and legal thresholds. The evaluation tool was divided into two parts: the technical testing and user experience testing.

The technical specifications were developed during the user experience workshops in Nairobi and tested under the real conditions in Taita Hills. Technical testing of applications touched on evaluating the technical capabilities of mobile applications, such as whether they allow for the capture of photos, calculation of land areas, whether they allow for flexible fields, etc., and other data that is most necessary in parcel mapping and land documentation.

Below are the minimal technical specifications that each tool should have to ensure a successful data collection process on parcels/land:

1. Contact: the ability to collect multiple contact details, such as name, ID, date and other custom fields.

The legal process, starting at the land registrar and across the board, requires the collection of identity documents and contact details of the applicant, information on the owner or multiple owners, information on the certified surveyor conducting the survey, and in case of land disputes, disputing parties.

2. Photo: the ability to take and upload photos into the system easily.

Taking a photo of the parcel or boundary points is essential for boundaries, especially for general boundaries in rural areas. Additionally, photo feature can be used to collect pictures of owners, neighbors, their IDs, signed documents, disputed areas, etc.

3. Flexible Fields: the ability to create new fields on the go.

Flexible Fields are one of the most important features for the usefulness of the application. There are several use cases for Flexible Fields:

* A plot can have more than one owner, or each plot can have a unique number of owners, neighbors, etc. Flexible Fields should allow the user to add as many fields as necessary.

* A boundary point or a boundary itself can be unique (maybe there is a dispute on the boundary or a surveyor needs to indicate an offset point). Flexible Fields should allow additional information to be attached on a feature.

* Different government bodies require different information. Depending on the purpose of the survey and the targeted government body, the user should be able to create their own form/fields based on the template form from the respective authority. For example, if the user needs to satisfy information for the Registrar of Lands or the Survey of Kenya, they should be able to use the template from the respective body as a guide to creating their own custom fields. This way it is ensured that relevant information is collected each time.

4. Preview/Review: the ability to allow for previewing of results.

Due to the amount of information gathered at each field visit a Preview/Review feature should be necessary.

5. Editing: the ability to allow for editing of information after review.

This feature is linked to the Preview/Review feature and it enables for correction of errors or to add more data if necessary. Given the legal sensitivity of the information gathered, the user should be able to correct mistakes, such as wrong spelling of names, or add additional data.

6. Map or aerial imagery integration: the ability to view, plot, edit, and review coordinates on the map.

A map or aerial imagery interface enables visual interpretation of the parcel in question. For example, aerial imagery can support mapping efforts through visual image identification of the parcel’s boundary points, features, amenities, etc. Locations of collected boundary points can be verified with the help of the imagery and, if necessary, manually moved to its proper location. Map integration enables for greater accuracy of mapping results.

7. Sharing: the ability to easily share information with other users.

One of the main advantages if ICTs is its ability to make information more transparent. In some instances, the officials representing a community can communicate on the process, progress, findings, etc. with each member of the community. Sharing of information also allows for collective custody of data, reducing the incidences of disputes and corruption. Sharing can promote openness, which in turn can lead to better relationships between neighbors.

8. Storage: the ability to save files both locally and on the cloud.

Most land administration documents in Kenya are recorded on and stored in paper format. This makes them vulnerable to risk, loss or damage, and susceptible to manipulation and fraud. Digitally stored data in the cloud can mitigate the above-mentioned risks.

9. Acreage: the ability to calculate the size of the area based on boundary points.

The parcel area size is one of the most sought for information by the landowners. Most landowners know the approximate size of their parcels. This information was often passed on to them through inheritance; however, a proper survey of land has rarely been carried out. The application should enable users to calculate area size based on the mapped boundary coordinates of the parcel (in Kenya acreage is the unit of reference for land ownership).

10. Remarks: the ability to add additional text.

Aside from these specific technical considerations, the user should have an opportunity to record any other observation that he or she deems necessary.

These are the technical specifications we developed and tested in the field. The next blog post will look at the user experience specifications.

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Introduction to User Experience Testing of Mobile Applications for Cadastral Surveys

We are currently in the midst of User Experience testing of our new mobile application, so I thought it might be useful to look back at the work we did a while ago on evaluating mobile tools/apps aimed at cadastral surveys and land/property mapping.

In 2017, Spatial Collective applied new technologies to the data capture element of land registration in order to test whether affordable tools for documentation of land exist, whether these tools can reach the accuracy standards required by the state, and whether communities can replicate the work of a professional surveyorTo do this, our research looked into the land demarcation process, determined whether new technologies were of quality and met national standards, and gauged the most cost-effective tools which are widely accessible to local communities.

Apart from the technical specifications of tools, the methodology for data collection and mapping, and legal specifications, the user experience had to be considered. Are people able to access the services they need? Are they able to use the tools available to them? Are these tools capable of collecting the necessary information, so that they do not waste people’s time and effort? Are the processes and methods accessible, replicable, and easy to use?

To answer some of these questions, we ran a User Experience workshop in Nairobi. The purpose of the workshop was to gather a more holistic understanding of the cadastral system in Kenya and to design an evaluation tool that can be used to scrutinize the mobile applications against the highest professional standards and legal thresholds. The workshop helped determine the immediate and long-term usability and accessibility of these tools to local people in data collection. It consisted of a design-thinking workshop, walkthroughs, and contextual interviews.

Design Thinking Workshop

The Design Thinking Workshop is a process led by a professional facilitator in which relevant stakeholders come together to deliberate about the issues at hand. The process aims to directly approach complex problems, gather insights, uncover frustrations and latent needs and put forth opportunities for innovation as seen from varying perspectives to create holistic, sustainable solutions with a human-centered focus.[1]

The participants of the design-thinking workshop were government and independent surveyors, high-end survey tool merchants, legal professionals, community leaders, and community members. The topic of the workshop was:

“Can widely available ICT’s such as mobile phones and off-the-shelf GPS units meet the professional survey and legal standards when used for land mapping?”

The dialogue provided a well-rounded understanding of the issues on surveying, land administration, and land mapping faced by various stakeholders.

Walkthroughs

Walkthroughs involve a thorough examination of specific steps taken to achieve a specific goal.

Several walkthrough exercises were facilitated with stakeholders to understand the process of land adjudication and registration of private and community land.

Contextual Interviews

Contextual interviews are personal interviews with stakeholders to uncover their individual perspectives, frustrations, desires, dreams, and goals. It also allows for the observation of stakeholders at work.

Several in-person interviews were conducted with government and private surveyors, community leaders, landowners, community members, and legal professionals.

Design of the Technology Evaluation Tool

Based on the user experience workshop, a tool for evaluating mobile applications for parcel/land mapping was designed. There was a particular focus on mobile applications as these are the most common technologies for on-the-ground data collection in development.

It was also evaluated whether selected applications allow for the capture of the most necessary attribute and spatial data on parcel/land, and user’s experience while using them. The evaluations can be divided into two parts:

  • Technical Testing
  • User Experience

Only two applications, GeoODK Collect and ESRI’s Geo-Collector, were tested. These represent two strands of software, Open Source and Proprietary, and are two applications which are often used in development. The following evaluation tool developed, however, can be used on any other application/tool. More about that coming in the next blog posts.

[1] See: http://design-thinking.org/en/index.html

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A neighborhood map

There is little accurate data about cities in Africa and a few effective methods to collect the same. Take Nairobi for example. Nairobi’s population has increased more than tenfold in the last 50 years. This rapid urbanization brought with it a two-tier development process where some areas are rapidly modernizing while others lag behind. Due to the speed with which the city is developing, there’s no easy way to understand and determine which areas are over- or underserved; there’s no easy way for people to share immediate experiences about neighborhoods.

Many data collection initiatives/tools that do exist are extractive and information rarely stays with the people. People are often cut out of the decision-making process, from determining what data points are collected to what happens with the data itself, and because of that, people don’t have access to data that is important to them. The failure to include the communities doesn’t just impact them negatively; it also reduces the accuracy of the data and knowledge about a place.

At Spatial Collective, we have been working on a platform that enables people to express their perceptions about a place through location, topic, and emotion. The spatial location means they can contribute information precisely in the area they are in. The topic section allows them to name or select which issue in particular matters to them. The emotion section allows them to say how they feel about the selected issue using their emotions with provision for further explanation. The platform does not dictate what is important about a place; the people will tell us.

Below are some preliminary results from Kibera.

The map above shows approximately one hundred perceptions from about half a dozen citizens of a small village in Kibera. The colors in the red specter are showing more negative perceptions/issues/feelings while the colors in the blue specter more positive.

If we focus on specific topics, such as security, waste, infrastructure, etc. we can extract very valuable data about a place. The map below shows only data that touch on waste and river in the area.  

Further, the map below displays a message touching on security at a specific open space inside the village.

Not everything needs to be negative. The next map below displays only positive perceptions of the people about a specific place in the village in Kibera. 

Finally, when we aggregate the data, we see the density of perceptions in each area of the village.

We are in the midst of platform development so more coming up soon.

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Open Cities Zanzibar

Open Cities Africa Project

Open Cities Africa is an initiative carried out in 10 cities in Sub-Saharan Africa, to engage local government, civil society, and the private sector to develop the information infrastructures necessary to meet 21st-century urban resilience challenges.

The project is aligned with the Global Facility for Disaster Reduction and Recovery’s (GFDRR) Resilient Cities Program and is implemented through a unique partnership between GFDRR and the World Bank, city governments, and a partner community comprised of regional scientific and technology organizations, development partners, and technology companies to support upcoming or ongoing World Bank-supported activities in the selected cities.

Zanzibar City

For the purposes of disaster risk management, the Revolutionary Government of Zanzibar (RGoZ), specifically the Commission for Lands (COLA) and the Department of Urban Planning, have noted the need to update their Zanzibar Master Plan with locations of all the built structures and flood-prone areas in the city.

Spatial Collective, the implementing partner of Open Cities Africa, spent many months on Zanzibar working with the local stakeholders and coordinating various data collection activities. The goal was to generate and visualize datasets critical to disaster risk management and to build the capacity of government staff, university students, and communities in the process.

The main objectives of this project were to:

  • Finalize the digitization of buildings on Unguja Island, the largest island of the Zanzibar Archipelago.
  • Ensure that the dataset was of acceptable quality by the stakeholders.
  • Assign building reference numbers to the entire dataset following very specific nomenclature put forth by the Zanzibar’s Commission for Lands.
  • Carry out community mapping of amenities and a household survey in six of Zanzibar City’s shehias or wards.
  • Provide a series of visualizations and in the process transfer knowledge to State University of Zanzibar (SUZA) and Zanzibar Commission for Lands (COLA) students and staff.

Digitization

Building upon the previous efforts, the main objective of the Open Cities Project on Zanzibar was to finalize the digitization of all the buildings on Unguja Island. For this reason, a digitization workspace with several computers and a localized network for accessing and sharing data was established at the Commission for Lands.

A dozen former students from the Zanzibar State University used the workspace to digitize about 160,000 buildings, mostly in Zanzibar City. These buildings were added to the pre-existing dataset of 200,000 buildings, completing the digitization of Zanzibar Archipelago’s largest island.

The entire dataset was re-checked for errors and building reference numbers were assigned following the nomenclature put forth by the Commission for Lands.

Fieldwork

After the digitization was complete, it was time for fieldwork. The aim was to collect data critical to the Commission for Lands’ urban planning efforts, specifically on flooding, waste management, and transportation.

The stakeholders agreed to carry out a household survey and GPS data collection in six shehias or wards. Twenty former State University of Zanzibar students, several Commission for Lands staff, and community representatives from each shehia were trained and participated in mobile and GPS data collection.

Altogether, 2,100 buildings were surveyed using Open Data Kit and ONA software. The data touched on registering building types, collecting basic demographic information, documenting people’s experiences of flooding, determining access to waste management services, and assessing transport patterns and habits of residents. GPS data collection of relevant amenities was also carried out in the area.

At the end of each day, the data was sent to the Zanzibar’s Commission for Lands where it was stored and visualized.

Capacity building

Likely the most important effort in this project was directed to working with existing data communities on Zanzibar and building capacity of University students and the Commission for Lands staff.

A dozen full-time digitizers were engaged between July 2018 and end of October 2018 and approximately 30 people were trained and participated in GPS and mobile data collection in January and February 2019. The trainees and data collectors were former SUZA students and COLA staff, community members, shehia administrators, and local emergency responders.

At least 25 training events were at the Commission for Lands touching on QGIS essentials, quality control and quality assurance, and OpenStreetMap.

To raise awareness about the project, half a dozen public events were held in and around Zanzibar City, and a large delegation from the Island attended both FOSS4G conference in Dar es Salaam and MapBox training on Zanzibar.

In February 2019, the Open Cities Zanzibar team had the privilege to present its work to the Director of Social, Urban, Rural and Resilience Practice at the World Bank.

Final Products

Between July 2018 and February 2019, 160,000 buildings were digitized and added to the pre-existing dataset of 200,000 buildings on Unguja Island, completing the digitization of Zanzibar Archipelago’s largest island.

The buildings were checked and corrected for errors and building reference numbers were assigned to each building. Several roads on Unguja Island and about 20,000 buildings on Pemba Island were also digitized.

In February, a household survey of about 2,100 households and GPS mapping within 6 shehias was complete. An interactive map of the area and several printed maps were made openly available. All the drone imagery is also made available to the public under a creative commons license.

Finally, a series of blog posts, social media posts, and manuals documenting and promoting Open Cities activities Zanzibar were written and shared with the public.

Way forward

Zanzibar has been through some sort of a renaissance of geospatial activities and open data in recent years. The whole archipelago was mapped using drones and hundreds of thousands of buildings were digitized just in the last two years. More importantly, dozens of youth worked on these projects, gaining crucial skills in mapping and other geospatial activities.

To keep the positive momentum going, it is crucial to develop a working environment for these emerging data and technology communities on Zanzibar. The Islands needs something like an urban laboratory, where creative ideas could come to fruition. A place like that could support the government in its endeavors and perhaps, more importantly, find innovative ways to share the data back with the people.

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Applying ICTs to the Data Capture Element of Land Registration: Lessons Learnt and Recommendations

This is the next in the series of blog posts on research into applying ICTs to the data capture element of land registration. It follows the previous blog post titled: Testing ICTs and Affordable Mapping Tools for Demarcation of Land Under Real-World Scenarios.

In our research conducted in 2017, we aimed to test whether:

  1. Cheap and widely available tools that can be used for land demarcation exist.
  2. These tools can reach the demarcation threshold required by the Kenyan government in terms of accuracy and attribution.
  3. Communities, using these tools, can replicate the work of a professional surveyor.

We find that cheap and widely available tools that can be used for land demarcation indeed exist. Kenya is a major technology hub of Africa. Mobile-cellular telephone subscriptions are higher than 80 percent and the percentage of individuals using the Internet was as high as 26 percent in 2016. These new technologies “help marginalized communities communicate, conduct business, receive nearly real-time feedback from crisis areas, alert populations about health risks, fight corruption, climate change, and alleviate poverty.”[1] Given the central role of communication costs in collective action, the growing abundance of cheap, broadly distributed and sophisticated information and communication technologies can affect the nature of collaboration in community-based development initiatives.[2]

When we tested a series of off-the-shelf GPS and mobile tools to see whether they can achieve the accuracy and attribution standards required by law, we found that environmental factors greatly affect the nature of measurements of different terrains. Lower accuracy and precision were observed in the forest with high canopy cover and low field of view for all devices. The measurements improved significantly as the environmental factors (canopy and terrain) improved, in the village and lowlands. Relatively high canopy cover and low field of view had the greatest effect on the measurements.

We find that these tools cannot reach the accuracy threshold required for demarcating fixed boundaries as these boundaries require three to four-centimeter accuracy under the Kenyan law. However, apart from the heavily forested areas, most devices were able to collect location data within three to five meters, as required for general boundaries.

Furthermore, we found that a pairing of mobile and GPS dependencies may provide the most optimal and cost-effective measurements in the face of environmental and terrain challenges and limited network connectivity.

Working with communities and a professional surveyor, we find that communities can lead the process of land demarcation and can replicate the work of a professional surveyor both in terms of accuracies and attribution required in rural areas (general boundaries). Smartphones can store the necessary attribute data from the field in a digital format, fulfilling the requirements to document people, land and associated rights.

We find that these tools provide an excellent alternative to the system that is currently used in rural areas where most parcels are registered only through pen and paper, and sometimes by measuring tape, and the information is stored in paper format at the County offices. The tools are also much cheaper and easy to use than the professional grade surveying equipment.

Some bottlenecks can be removed by using these affordable technologies:

  • Lack of affordable tools.

The tools are widely available, affordable, and easy to use by communities.

  • Local communities have no access to information.

With these tools, information can be easily collected, stored and shared.

  • Local communities are not able to value their land.

Applications can be built to streamline the valuation of land based on the data input.

  • The registration process is unclear or unknown to the communities.

The tools can be used for information sharing.

  • The relationships between Kenyan national, community and individuals in terms of property rights is difficult for communities to comprehend.

This is a systemic issue that the tools cannot address on their own.

  • Antiquated procedures sustained through inertia in the titling process and an inability to explore, let alone adopt new technologies to replace old methods.

This is still an issue in Kenya, however, the tools provide for an excellent alternative to the current system of paper-based data storing, etc.

  • Technical tools used to capture vital information on mapping are often too expensive, difficult to operate, rely solely on connectivity, and require extensive training/maintenance and complex processing solutions. In some cases, the skills needed to record information accurately often built up over many years of experience including formal qualifications.

Training is relatively simple and most processes repeatable to a satisfactory standard, and the possibility of having units available at sub-county level that can be rented out to communities makes it cost effective and affordable.

As practitioners, we see the need for simplification and streamlining of the functionality of various hardware and software used for documentation of community lands. The use of affordable and widely available ICT tools can empower local people to rightfully claim land and thus eradicate future land disputes and conflicts amongst them. There are ample opportunities for policymakers, lawmakers, technical experts, and administrators to use these insights to influence and shape their land rights agendas, as well as support efforts to better include local people and accurately map boundaries in Kenya.

Authors: Primoz Kovacic, Michelle Gathigi, Justus Muhando, Alan Mills

 

[1]Kovacic, Primoz. 2014. Digitally Enabled Collective Action in the Areas of Limited Statehood, Implications of Information and Communication Technology for Collective Action on Hazard Mitigation and Environmental Management in Mathare, Kenya. Masters Thesis

[2]Kovacic, Primoz. 2014. Digitally Enabled Collective Action in the Areas of Limited Statehood.

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Testing ICTs and Affordable Mapping Tools for Demarcation of Land Under Real-World Scenarios

This is the next in the series of blog posts on research into applying ICTs to the data capture element of land registration. This blog post follows the previous blog post was titled: Testing ICTs and Affordable Mapping Tools for Demarcation of Land under Ideal Conditions.

In the previous post, we looked at how some available and affordable ICTs and GPS units behave under ideal environmental conditions. We measured each tool’s relative accuracy and precision over a known trigonometric point in Nairobi. In this blog post, we examine how these same tools behave under varying environmental factors.

Study Locations

Beyond their technical specifications, the performance of each tool to collect location data is affected by a variety of environmental factors, in particular, those narrowing the field of view to obtain mobile connectivity or be in the line of sight of GPS satellites.

For the purpose of this study, simple accuracy and precision tests were done in 2017 in Taita Hills, Kenyan Coastal Region. The hills provide a number of locations within a compact study area that gives a variety of environmental conditions, namely:

  1. Forested land in the hills (high altitude).
  2. Village communities consisting of subsistence farming in the hills (between highlands and lowlands).
  3. Savannah, relatively flat farmland with an open canopy (lower altitude).
  4. Urban environment represented by the town of Voi (lower altitude).

Point Measurements under Varying Conditions

Our particular interest was how canopy cover, terrain, mobile connectivity (for mobile devices), and survey conditions, affect accuracy and precision measurements of boundary points of parcels.

The purpose of this exercise was not to conduct rigorous scientific measurements of each tool but rather to test how the environment affects the measurements of locations with a specific focus on the demarcation of land.

Eight sites with varying environmental conditions were selected for testing. At each site, a reference point was measured with Leica Real Time Kinematic GPS which is capable of very precise measurements (up to a millimeter). Each device was then placed on top of the reference point where location data was continuously collected for about 10 minutes. We find that environmental factors significantly affect the nature of measurements. Lower accuracy and precision were observed in the forest with high canopy cover and low field of view for all devices. The measurements improved significantly as the environmental factors (canopy and terrain) improved, in the village and lowlands. Relatively high canopy cover and low field of view had the greatest effect on the measurements.

Variable network connectivity conditions were observed in the village and in the forest; however, as the first test in Nairobi showed, network connectivity did not have a significant effect on improving accuracy and precision of measurements.

A much higher relative accuracy and precision were obtained by the two GPS devices (Bad Elf and Garmin) compared to the mobile devices. These two devices have superior GNSS chipsets to those of the mobile phones.

If we place top ten measurements for each device on the horizontal line that indicates the distance measured from the reference point, we see that the measurements have higher accuracy (proximity to reference point) and precision (proximity to each other) under the more favorable environmental conditions (canopy cover and terrain).

How do these findings affect individual parcel measurements?

If the previous tests give practitioners a rough idea of what to expect in terms of each device’s relative accuracy and precision as they relate to various fieldwork conditions, the next test indicates how this affects the capture of boundary points and the demarcation of individual parcels.

For this experiment, ten parcels with varying environmental conditions were measured with a Survey grade GPS unit (Leica1200 with RTK) for reference. At each reference boundary point, the location was obtained using one of the devices, and specific records of the terrain, canopy cover, network availability, time of data capture, and ability to collect a point on each application were recorded.

Ten parcels were measured using Garmin e-Trex and Bad Elf GPS units, Samsung S7, Infinix Zero 4 Plus, Samsung Tablet, and an iPhone, and overlaid on top of parcels measured with professional grade Leica GPS. Below are the results from some of the parcels.

If we compare the areas of parcels measured with each device, we see that the difference in the areas measured changes based on environmental factors. In these measurements, we combined the canopy cover and field of view into one indicator called Canopy Cover expressed in percentage points. As demonstrated in this chart, the results improved when the field of view increased and canopy cover decreased.

According to one professional surveyor:

Canopy cover and field of view are two things that influence the GPS measurements the most.

Did these selected affordable tools reach the threshold in terms of accuracy?

The answer is yes and no.

These tools cannot reach the accuracy threshold required for demarcating fixed boundaries as these boundaries require three to four-centimeter accuracy under the Kenyan law. Apart from the professional grade GPS unit, none of the tools reached this level of accuracy. However, apart from the heavily forested areas, most devices were able to collect location data within three to five meters, as required for general boundaries.

Next blog post will look at whether the communities can replicate the work of a professional surveyor using these technologies.

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Testing ICTs and Affordable Mapping Tools for Demarcation of Land Under Ideal Conditions

This is the next in the series of blog posts on research into applying ICTs to the data capture element of land registration. The previous blog post was titled: Technical Thresholds Required for Demarcation of Individual and Community Land in Kenya.

The idea of communities demarcating their own land is predicated on a series of assumptions:

  1. That cheap and widely available tools that can be used for land demarcation exist.
  2. That these tools can reach the demarcation threshold required by the Kenyan government in terms of accuracy and attribution.
  3. That the communities, using these tools, can replicate the work of a professional surveyor.

To test these assumptions, we conducted a series of experiments in 2017 in Taita Hills, Taita Taveta County.

We first examined the process of demarcating land both for new grants and for subdivision of land. We described these in the previous blog post. Specifically, we focused on the accuracy and attribution of spatial data required by the professional surveyor and government offices.

Second, we completed a series of tests of affordable and ubiquitous technologies for capture and demarcation of land to see whether they achieve the thresholds required. We tested these tools under varying environmental conditions to see how they affect the measurements. We will describe the findings in several upcoming blog posts, starting with this one.

Finally, we assessed whether communities can replicate the demarcation of land by the professional surveyor using these tools. We did this experiment by allowing community members to follow the professional surveyor and replicate his work.

The first test of the tools was done under what can be considered ideal conditions with a clear field of view and good mobile network connectivity. We found that even under these conditions there’s a certain level of accuracy and precision of location measurements that each tool can achieve. Accuracy refers to the closeness of a measured value to a standard or known value and precision refers to the closeness of two or more measurements to each other.

When we placed our GPS units and mobile phones above a known trigonometric point to demonstrate what type of accuracy and precision can be achieved in ideal circumstances, we found that accuracies and precision of tools vary.

As we can see, the points taken with GPS units (BadElf and Garmin) fall between 1 and 3 meters from the known trigonometric point while the points taken with mobile devices fall between 1 and 5 meters.

The measurements of GPS devices are relatively precise, especially the measurements of the Bad Elf GPS unit. The precision is indicated by the closeness of points on the horizontal line. We also noted that access to the network data (with or without data) does not affect the accuracy or precision of the measurements of mobile phones.

Next blog post will describe testing in so-called real-world scenarios.

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