Create a link map

In this lesson, you're a reporter working on a story about how the refugee crisis developed over time. You're looking for patterns to help you better understand the movement of refugees, asylum-seekers, and internally displaced persons when they are forcibly displaced from their homes.

To do so, you'll look at the movement of refugees using a flow map. You'll create a new ArcGIS Insights workbook and use boundaries from ArcGIS Living Atlas of the World to enable location on a Microsoft Excel file. Then, you'll create a link map and change the settings so that the map shows the best information for your analysis.

Add data

First, you'll download a spreadsheet of population statistics compiled by the United Nations High Commissioner for Refugees (UNHCR). Then, you'll sign in to Insights and add the data to a new workbook.

  1. Download the UNHCR_1951_2020 Excel file.
  2. Locate the downloaded file on your computer.
    Note:

    Depending on your web browser, you may have been prompted to choose the file's location before you began the download. Most browsers download to your computer's Downloads folder by default.

    The downloaded file is a spreadsheet. Next, you'll create a workbook in ArcGIS Insights.

  3. Sign in to your Insights in ArcGIS Online account or Insights in ArcGIS Enterprise account.
    Note:

    To access Insights in ArcGIS Online, your ArcGIS organization's administrator must grant you a license for it. If your organization does not have Insights licenses, you can sign up for a free trial.

    To access Insights in ArcGIS Enterprise, your organization's administrator must grant the necessary license and privileges for it. For more information, see Administer Insights in ArcGIS Enterprise and Insights in ArcGIS Online. Once the license and privileges are granted, you need to sign in to your ArcGIS Enterprise account, and you should be able to view the app in the app launcher.

    If this is your first time using Insights, the Welcome to Insights window appears with a list of things you can do with Insights.

  4. If necessary, in the Welcome to Insights window, click Skip.

    The Insights home page appears.

  5. Click the Workbooks tab.

    Workbooks tab

    The Workbooks page appears. Depending on your previous use of Insights, this page displays the workbooks that you already created or that were shared with you by members of your organization.

  6. At the top of the page, click New workbook.

    New workbook

    Note:

    If you do not see the New workbook button, your account may not be the Publisher role required for this lesson. You can request a role change from your administrator.

    The Add to page window appears. You'll add two datasets to your workbook: one from the Excel spreadsheet you downloaded and one from ArcGIS Living Atlas.

  7. On the Data tab, click Upload file.

    Files on Data tab

  8. Click Browse my computer. Browse to and add the UNHCR_1951_2020 spreadsheet.

    The spreadsheet is added to the Selected Data pane. The Persons of Concern table contains data about the movement of people between countries. You'll also add a layer of countries from ArcGIS Living Atlas. Later, you'll join your table to the layer to display it spatially.

  9. Click the Living Atlas tab.

    Living Atlas option

    ArcGIS Living Atlas contains a wide variety of authoritative data from around the world. You'll search for the layer you want.

  10. In the search bar, type Countries and press Enter.

    The search returns one result named World Countries (Generalized) by esri_dm.

  11. Click the orange World Countries (Generalized) result.

    Add World Countries (Generalized).

    The layer is added to the Selected Data pane.

  12. Click Add.

    The datasets are added to the data pane of a new workbook. The countries are also added to a map card named Card 1. This map card doesn't contain information from the Persons of Concern table, so it's not useful. You'll remove it.

  13. Click the Card options button and choose the Delete button.

    Delete button

    The card is deleted.

Enable location

Next, you'll enable location on the Persons of Concern table using the layer of countries. You'll need to enable location for two fields in particular: the field that indicates country of asylum or residence (where persons of concern went) and the field that indicates country of origin (where persons of concern came from).

  1. In the data pane, click the arrow to expand Persons of Concern.Table1.

    Expanded Persons of Concern table

    The dataset includes string and number fields, but no location fields.

  2. For Persons of Concern.Table1, click the Dataset options button and choose Enable location.

    Enable Location option

    The Enable location pane appears.

  3. Click the Geography tab. Change the following parameters:
    • For Location fields, choose Country of asylum.
    • For Matching geography level, choose World_Countries_(Generalized) (the ArcGIS Living Atlas layer).

    Enable location pane

    The Estimated match accuracy indicator provides a visualization of how many rows in the table can be successfully joined to the geography layer. In this case, most rows in the Country of asylum field have a match.

  4. Click Run.

    A location field named World_Countries_(Generalized) is added to the table.

    Location field added

  5. Point to the World_Countries_(Generalized) field and click the Rename field button.

    Rename field button

  6. Rename the field Country of residence and press Enter.

    You've enabled location for the field that indicates where refugees and asylum-seekers currently reside. Next, you'll enable a location field that indicates their country of origin.

  7. For Persons of Concern.Table1, click the Dataset options button and choose Enable location.
  8. In the Enable location pane, on the Geography tab, change the following parameters:
    • For Location fields, choose Country of origin.
    • For Matching geography level, choose World_Countries_(Generalized).
  9. Click Run.

    The new field is added. Like the previous field, this one has a default name of World_Countries_(Generalized).

  10. Rename the World_Countries_(Generalized) field Country of origin.

    The table now has two location fields, one for country of origin and one for country of residence. Next, you'll rename and save the workbook.

  11. On the ribbon, click Untitled Workbook, type UNHCR Population Statistics, and press Enter.
  12. On the workbook toolbar, click the Save button.

    Save button

Create a link map

Link maps focus on relationships and connections in a dataset. They use nodes and lines or arrows to display relationships between locations. You'll create a link map in which the nodes are country of origin and country of residence and the links are the total number of persons of concern moving between them.

You'll start by calculating a field with the total population of persons of concern.

  1. For the Persons of Concern.Table 1 dataset, click the Dataset options button and choose View data table.

    The data table appears.

  2. Click + Field to add a new field to the table.
  3. Click the field name (New Field) to make it editable. Type Total population and press Enter.
  4. In the Enter calculate function box, copy and paste the following equation:

    asylum_seekers+idps_of_concern_to_unhcr+others_of_concern+refugees_under_unhcr_s_mandate+returned_idpss+returned_refugees+stateless_persons

    The equation adds all of the number fields in the table to give the total number of persons of concern.

  5. Click Run. When the field calculation completes, close the data table.

    The Total population field is added to the Persons of Concern.Table1 dataset.

  6. In the data pane, click the circles next to the Country of origin location field, Country of residence, and Total population.
    Note:

    Be sure to select the fields in the order listed in the instruction, not the order they appear in the data pane.

    Selected fields

  7. Drag the fields to the page and drop them in the Map drop zone.

    Fields dragged to Map drop zone

    All selected fields are added at once.

    Tip:

    You can also click the Map button above the data pane to create the link map.

    A link map is created with nodes representing countries and links representing the number of persons of concern who have moved between the countries. In this case, the map uses arrows to show the direction of the movement of migrants. Link maps with directional relationships are called flow maps. Next, you'll change the map's settings so that it displays the information more effectively.

  8. On the map card, next to the Persons of Concern.Table1 layer name, click the arrow button.

    Arrow to view Layer options pane

    The Layer options pane appears. This pane shows an arrow pointing from the country of origin to the country of residence, as well as several parameters.

    Note:

    If the fields were selected in the incorrect order, the arrow may point in the opposite direction (from country of residence to country of origin). To change the direction, click the link (the arrow between the two nodes) and click the Flip button.

    The nodes, which represent the countries of origin and the countries of residence, are sized by graduated symbols using a method called centrality. The default centrality is measured by outdegree (the centrality measure is displayed in the Layer options pane, on the Symbology tab, under the Graph options parameter).

    The outdegree refers to the number of outgoing links a country has. A country whose refugees settle in many different countries will have a larger symbol than countries whose refugees leave to settle in one or two countries. The outdegree does not specify how many people are leaving a country, only how many outgoing links the country has.

  9. In the Layer options pane, for Size nodes using, choose Indegree.

    Size nodes using Indegree

    The Indegree option refers to the number of countries from which a country accepts refugees and asylum-seekers. A country that accepts refugees and asylum-seekers from many countries will have a larger node than a country that accepts refugees and asylum-seekers from one or two countries. The node size does not refer to the number of persons of concern in the country of residence. The indegree will be useful for your story because it provides information about which countries have asylum-seekers from across the world.

    Next, you'll change the style of the nodes so that they are easier to interpret.

  10. In the Layer options pane, click the Country of origin node to select it. Click the Appearance tab.

    Appearance tab for the Country of origin node

    Note:

    Since both location fields are based on countries, the nodes are styled using the same symbol by default. The style of both nodes will be changed even if only one node is selected.

  11. Under Node style options, for Fill color, choose no fill.

    Change the nodes to no fill.

  12. For Outline color, choose the purple color in the second row, second-to-last column (hex value #DF73FF).

    Change the node outline to purple.

  13. Change the Outline thickness to 1.5 px.

    Node Outline thickness

    Next, you'll change the links to a lighter color.

  14. In the Layer options pane, click the link (arrow) to select it.

    Link style options

  15. Under Link style options, for Color, choose the gray color in the first row, second column (hex value #858585).
  16. Close the Layer options pane.

    Last, you'll change the basemap. The link map is meant to highlight the relationships between nodes, so you'll choose a basemap with a muted background.

  17. On the workbook toolbar, click the Basemaps button and choose Light Gray Canvas.

    Basemaps button

  18. Click a blank area on the page to deactivate your map card.

    The map card's title, Card 1, is displayed in place of the card toolbar.

  19. Click the Card 1 text, type Migration of persons of concern, and press Enter.

    Renamed link map

  20. Save your workbook.

You've enabled location on a nonspatial dataset and used the data to create a flow map, which shows the movement of persons of concern from their country of origin to their country of residence.


Add nonspatial cards

Previously, you added a spreadsheet to a new workbook and used it to create a map card. Next, you'll create cards that will improve your understanding of the flow map and help you visualize specific relationships. First, you'll create a predefined filter that will allow you to choose which year to analyze. Next, you'll create charts to display the total count of persons of concern in each country of origin and country of residence. Then, you'll create a summary table to compare the number of refugees and the number of internally displaced persons.

Create a predefined filter

The link map you created is currently showing all the data collected by the UNHCR from 1951 to 2020, making it difficult to see any patterns or relationships in the data. A predefined filter can be used to manage the data so that it can be analyzed more effectively.

  1. If necessary, open your UNHCR Population Statistics workbook.
  2. On the workbook toolbar, click the Widgets button and choose Predefined filter.

    Predefined Filter option

    A predefined filter card is added to the page.

  3. In the Predefined Filter 1 card, click Add.

    Add button

    The New filter pane appears.

  4. For Filter by, under Persons of Concern.Table1, choose Year.

    Filter by Year field

    A list of all values in the Year field is added to the pane. The list spans from 1951 to 2020. You can add the values individually or by groups.

  5. Click By value.

    By value button

    The Predefined Filter 1 card is updated with the years 1951 to 2020. The boxes can be selected to filter data to the selected years.

  6. Drag the year filter card below the Migration of persons of concern card.

    Year filter card moved below the map card

    The data you are using from the UNHCR gives the total number of persons of concern for each year, rather than the new persons of concern for each year. For example, a person who is documented first as a refugee in 2018 could be counted as a refugee again in 2019 and 2020 if their status has not changed. Therefore, it is important to avoid any analysis that aggregates data from multiple years, because you'll end up with artificially high totals. The filter settings can be used to ensure that only one year can be chosen at once.

  7. On the year filter card, click the Card options button and click the Appearance button.

    Appearance button

    The Appearance pane appears.

  8. Click the Selection properties tab.

    The Selection type options are displayed. By default, Multi select is selected.

  9. Click Single select.

    Single select option

    The Selection type changes so that only one year can be selected at a time.

  10. Close the Appearance pane.

    The filter is updated to a single select layout, with 1951 selected by default. The flow map is updated to show several nodes that are the same size, but with no link connections. This is because the UNHCR did not collect data on country of origin until 1960 (the origin is recorded as Various/Unknown).

    Map showing data from 1951

  11. On the year filter card, scroll down and click 2020.

    The map updates to show the persons of concern from 2020.

    Map showing data from 2020

  12. Rename the filter card Year.
  13. Save your workbook.

Add charts and tables

The predefined filter has made some aspects of the link map clearer. However, there is still a lot of information that you cannot learn from the map. For instance, you can use the flow map to determine which countries accepted refugees from many countries, but it's not possible to tell which countries have the largest number of persons of concern. Chart and table cards can supplement the flow map and make your analysis more effective. For the purpose of your story, it will be important to know where persons of concern are living.

To understand which countries have the greatest number of persons of concern, you'll add chart and table cards to the workbook.

  1. In the data pane, under Person of Concern.Table1, select the Country of asylum and Total population fields.

    Selected fields

  2. Drag the selected fields to the empty space next to the map card, point to the Chart drop zone, and choose Bubble Chart.

    Bubble Chart option

    A bubble chart is created. It shows the population of persons of concern in each country of residence. Like the link map, it is filtered by the predefined filter.

  3. Rename the bubble chart card Country of asylum.

    Bubble chart showing the country of residence and persons of concern in 2020

    If your filter is set to 2020, the bubble chart shows that Colombia, Congo, and Syria are the countries with the highest total populations of persons of concern.

  4. Click the bubble for Colombia (abbreviated Colom).

    Colombia selected on the bubble chart

    The link map updates to show the nodes and links where Colombia is the country of residence. The thickest line both originates in and points to Colombia. The rest of the lines are thinner, so it's difficult to know how many people are coming from the other origin countries. You'll need to create another chart for the country of origin.

    Persons of concern residing in Colombia

  5. In the data pane, under Persons of Concern.Table1, select the Country of origin string field (not the location field) and Total population field. Drag the selected fields to the empty space next to the bubble chart, point to the Chart drop zone, and choose Column Chart.
    Note:

    You can change which statistics are displayed on the chart using the Chart statistics button on the card toolbar. You can even remove all statistics.

    Column Chart option

  6. Rename the column chart Country of origin. Click the card to select it and drag a side of the card to increase the card's width.

    Some of the columns on the column chart are faded. The columns that remain indicate countries that have persons of concern residing in Colombia. However, the chart still doesn't show the number of people from each country of origin that are residing in Colombia, only the total number of persons of concern for each country, regardless of where they reside.

    Countries with persons of concern living in Colombia

    To understand the flow of migrants at the country level, you'll need to apply a cross filter. A cross filter will filter your cards based on selections on other cards.

  7. Click the Enable cross filters button on both the bubble chart and the column chart.

    Enable cross filters on bubble chart

    The column chart is filtered to show the countries of origin for persons of concern living in Colombia.

  8. Point to the bars to see the number of persons of concern.

    The other countries' bars appear to have disappeared, but actually, the bars are too small to see in comparison to the Colombia column. There are almost 9.5 million persons of concern from Colombia residing in Colombia. The country with the next highest number of persons of concern living in Colombia is Venezuela, with about 20,000.

  9. On the bubble chart, deselect Colombia.

    The filter is removed from the column chart. The tallest column on the chart is Syria. In 2020, Syria had the highest total persons of concern for any country of origin, over 13.6 million.

  10. Select the Syria column.
    Tip:

    Point to a column to see the name of the country.

    Syria column selected

    The link map reflects the selection, and the bubble chart is filtered because of the cross filter.

    Country of residence for persons of concern from Syria

    Note:

    You can also apply the cross filter to the link map. A cross filter will make the map easier to read, but it will also change the nodes so that they are all the same size.

    According to the bubble chart, Syria is the country of residence with the most persons of concern from Syria, which implies that internally displaced persons make up a large portion of the total population. However, as a reporter, it is important that you work with facts, not assumptions. To make sure your assumption is accurate, you'll create a summary table.

  11. Deselect the Syria column. Deselect the column chart.
  12. In the data pane, select the Country of origin (string field), Country of asylum (string field), Refugees under UNHCR's mandate, Asylum-seekers, IDPs of concern to UNHCR, and Total population fields.

    Selected fields to create a summary table

  13. Drag the selected fields to the Table drop zone in the empty space next to the year filter card and choose Summary Table.

    Table drop zone

    A summary table is created, but it is hard to read the values. The table will have to be resized.

  14. Confirm that the table card is selected. Drag the sides of the card to increase the width of the table.

    Increase width of the table.

  15. In the data pane, point to each of the following fields, click the Rename field button, and rename the fields as follows:
    • For Country of origin, type Origin.
    • For Country of asylum, type Residence.
    • For Refugees under UNHCR's mandate, type Refugees.
    • For IDPs of concern to UNHCR, type IDPs.

    Update field names in data pane.

    The field names also update in the table.

    Field names updated in table

  16. Select the table card. On the toolbar, click the Enable cross filters button.

    Enable cross filters for table card.

  17. Collapse the column headers and hide the card header.

    Buttons to collapse column headers and hide card header

  18. Save the workbook.

You've created a predefined filter, charts, and a summary table that can be used to examine the data and learn more about persons of concern.


Interpret patterns using link analysis

Previously, you created nonspatial cards and filters. Next, you'll use the maps, filters, charts, and tables to look for patterns in your data. You'll also interpret those patterns by performing link analysis and looking for discrepancies between situations with similar types of conflicts and changes over time.

Analyze current refugee situations

In 2020, the countries of origin with the highest total persons of concern were Syria and Colombia. You'll use the charts created in the previous section to find out more about the situations in those countries.

  1. If necessary, open your UNHCR Population Statistics workbook and confirm that 2020 is chosen on the predefined filter.
  2. On the column chart, select the Syria column.
  3. On the map card, zoom to Syria.

    Persons of concern originating in Syria

    Tip:

    Use the scroll wheel on your mouse to zoom or press and hold Shift while drawing a box around Syria on the map to zoom. If you click selected features when you pan or draw the box, the features will be dragged when you move your mouse. This functionality is one of the drag-and-drop features in Insights that can be used to create new maps, charts, and tables from the selections on your cards. Therefore, you will have to click your mouse over an area of the map that does not have selected lines or nodes on it.

    The bubble chart and summary table are both filtered to show the countries where persons of concern from Syria were residing in 2017. You can also click the arrows next to the column name in the summary table to sort the columns in ascending or descending order.

    According to the calculations at the bottom of the table, there are over 6.6 million refugees, 107,000 asylum-seekers, and 6.7 million internally displaced persons from Syria, totaling over 13.6 million persons of concern. There are other categories of persons of concern in the UNHCR data that are not present on the table, including returned refugees, returned internally displaced persons, stateless persons, and others of concern, which is why the sum of the total population is slightly larger than the sum of refugees, asylum-seekers, and internally displaced persons. The majority of the data is in the refugees, asylum-seekers, and internally displaced persons fields, so you'll only be using those fields in the table for now.

    Table showing Syrian persons of concern in 2020

    On the map, the thickness of the links between Syria and the country of residence indicate the number of persons of concern moving between those countries. The thickest line is the loop back to Syria, which represents mostly internally displaced persons. The next thickest lines are to Turkey, Lebanon, Jordan, and Germany. These four lines represent approximately 86 percent of the refugees from Syria.

    The flow map uses the Total population field, so how does Insights know how many persons of concern there are internally in Syria? The flow map pulls data from the Total population field, visualized as line widths, and links it to country of origin and country of residence locations. However, displaying the data spatially gives more context and information that helps you to understand the data better.

    Turkey, Lebanon, and Jordan all share a border with Syria, which indicates that proximity plays a major role in where refugees are residing. The other neighboring countries are Iraq and Israel; according to the summary table, Iraq had the fifth largest number of refugees in 2020 behind Germany, but Israel only had five Syrian refugees, despite the proximity of the two countries. Unfortunately, the data cannot tell you why the number of refugees in Israel is so much smaller than in the other neighboring countries. You'll have to do more research if you want to find out why.

    Besides giving information about the number of migrants between each country, the flow map also has information about how many countries the refugees are coming from through the centrality in the nodes.

  4. On the map card, point to the node for Turkey.

    Normalized indegree of Turkey

    A pop-up appears and shows that Turkey has an indegree centrality of 0.02. The centrality numbers are normalized, meaning they are showing the proportion of countries of origin to which each country of residence is connected. There are many reasons to use normalized centrality values, such as comparing values across networks with different sizes. In this example, normalization is not necessary and not intuitive. You'll turn off normalization on the nodes.

  5. On the map card, for the Persons of Concern.Table1 layer, expand the Layer options pane. On the Options tab, uncheck Normalized.

    Normalized parameter

  6. Close the Layer options pane.
  7. Point to the nodes for Turkey, Lebanon, Jordan, and Germany.
    Tip:

    You may need to pan or zoom the map to see the node for Germany.

    Indegree centrality of Turkey

    The indegree centralities for Turkey, Lebanon, Jordan, and Germany are now 4, 39, 43, and 159, respectively.

  8. On the column chart, deselect Syria.

    Colombia has the second highest number of persons of concern, according to both the bubble chart and the column chart. You will repeat the analysis for Colombia.

  9. On the Country of origin chart, select Colombia (the second highest column).

    Colombia selected on the column chart

    The map shows Colombia as the country of origin. Zoom and pan to northern South America and center your map on Colombia. Unlike Syria, it is difficult to tell which lines are thickest because the number of internally displaced persons is so much larger than the number of refugees in other countries of residence. You'll have to rely on the summary table to find the countries with the most refugees from Colombia.

  10. On the summary table, next to Total population, click the arrows twice.

    Sort Total population in descending order.

    The column is sorted in descending order, with the countries that have the highest number of persons of concern shown first. Colombia has 8.25 million internally displaced persons and almost 190,000 refugees. The countries with the most persons of concern from Colombia are Ecuador, Venezuela, Spain, and the United States.

    Ecuador and Venezuela both neighbor Colombia, but Spain and the United States do not. However, the number of persons of concern in Spain and the United States is much lower than the number in Ecuador and Venezuela, so the pattern of refugees residing mostly in neighboring countries that you saw with Syria is still consistent for Colombia.

  11. On the map card, point to the nodes for Ecuador, Venezuela, Spain, and the United States.
    Tip:

    You can use the Default extent button to zoom to the map's original extent, rather than panning to Spain and the United States.

    The indegree centrality values for Ecuador, Venezuela, Spain, and the United States are 67, 23, 106, and 182, respectively. Based on the other information in the node pop-up, the maximum centrality in 2020 was 182, meaning the United States had the highest indegree centrality of any country.

    For both Syria and Colombia, the country of origin had the largest number of persons of concern, which indicates a high number of internally displaced persons.

    Another pattern seen in both countries is that persons of concern tend to travel the shortest distance to find refuge, such as Syrians finding refuge in the neighboring countries of Turkey, Lebanon, and Jordan. The exceptions are countries such as the United States and Germany, which are countries known to have large immigrant and refugee populations, or Spain, which shares a common language with Colombia. These countries, therefore, have higher indegree centralities than countries who mostly take in persons of concern from neighboring countries, despite often taking in lower numbers of persons of concern.

    These trends do not explain the cause of the human flows, but they serve as a starting point for further investigation. Global affairs, war, politics, foreign policies, and other factors all influence what boundaries people are allowed to cross.

  12. In the column chart card, deselect Colombia.

Analyze similar refugee situations

In 2017, the UNHCR called the violence against Rohingya Muslims in Myanmar a "textbook example of ethnic cleansing." Next, you'll look closer at the data for Myanmar and compare it to past conflicts involving ethnic-based genocides to determine if any patterns emerge among similar types of conflicts.

You'll analyze data from the current conflict in Myanmar and the Rwandan genocide. Because you already know what data you will be analyzing, you can create a new predefined filter to make it easier to switch between the two countries.

  1. On the workbook toolbar, click the Widgets button and choose Predefined filter.

    The Predefined Filter 1 card is added to the page. You may need to scroll down the page to see the new filter.

  2. On Predefined Filter 1, click Add.

    The New filter pane appears.

  3. Click Choose a field. Under Persons of Concern.Table1, choose Origin.

    Filter by Origin field.

  4. Uncheck Select All.

    Uncheck Select All.

    All of the countries are deselected.

  5. In the search bar, type Myanmar. In the list of results, check Myanmar.

    Myanmar search result

  6. Search for Rwanda. In the list of results, check Rwanda.
  7. Click By value.

    The two selected values are added to the filter.

    Origin filter

  8. Rename Predefined Filter 1 to Origin. If necessary, resize the card and move it to a convenient place on your page.
  9. On the Origin filter, uncheck Rwanda. The year filter should still be set to 2020.

    The page is filtered to show data for Myanmar in 2020.

    Unlike in the previous section, the largest group of persons of concern who left Myanmar is refugees. The second largest group is internally displaced persons. In the other countries you looked at, the largest group was internally displaced persons.

    Table of persons of concern from Myanmar

    Based on the flow map, the refugees from Myanmar seem to reside in fewer countries than refugees from the previous countries you looked at. You'll quantify the pattern by changing the centrality of the nodes from Indegree to Outdegree.

  10. On the Migration of persons of concern map card, for the Persons of Concern.Table1 layer, expand the Layer options pane. On the Symbology tab, change Indegree to Outdegree.

    Display the nodes by outdegree.

    Until now, the Migration of persons of concern map did not have a filter applied because filtering the data would affect the indegree calculations. Now that the centrality has been changed to Outdegree, the centrality of the origin nodes will not be affected when filtered by the country of origin.

  11. Close the Layer options pane. Zoom to Myanmar and point to the Myanmar node.

    Outdegree centrality for Myanmar

    The outdegree for Myanmar is 43, meaning persons of concern from Myanmar were residing in 43 countries in 2020.

    Next, you'll look at the yearly data starting in 2015 to see if there are any patterns in the outdegree centrality or in the number of persons of concern leading up to the conflict and after the conflict began in 2017.

  12. On the year filter, click 2015.
  13. On the Migration of persons of concern map, point to the node for Myanmar.

    The outdegree is 45. The summary table indicates that there are 451,804 refugees, 60,632 asylum-seekers, 451,089 internally displaced persons, and 989,233 persons of concern in total.

  14. Use the year filter, the map, and the summary table to find the centrality and numbers of persons of concern for 2016 through 2020.

    The following table summarizes the data for the specified years:

    YearOutdegree centralityRefugeesAsylum-seekersInternally displaced personsTotal population

    2015

    45

    451,804

    60,632

    451,089

    989,233

    2016

    43

    490,285

    56,023

    375,016

    923, 007

    2017

    43

    1,156,742

    41,088

    353,108

    1,551,731

    2018

    42

    1,145,149

    30,459

    370,306

    1,546,484

    2019

    40

    1,076,825

    37,534

    312,018

    1,429,012

    2020

    43

    1,103,299

    40,207

    370,320

    1,516,974

    There is a lower outdegree in 2016 and 2017 than in 2015, despite 2017 having the largest number of refugees. The number of refugees increased by over 600,000 from 2016 to 2017, and then stayed fairly consistent through 2020. The number of internally displaced persons decreased slightly each year until 2018, when the number began to fluctuate each year.

    You will take a closer look at the data in 2016 and 2017, the years when the number of refugees more than doubled.

  15. Use the year filter and the summary table to compare the number of refugees in Bangladesh in 2016 and 2017.

    The number of refugees from Myanmar in Bangladesh increased from 276,198 to 932,204 from 2016 to 2017. The increase in Bangladesh accounts for the overall increase in the number of refugees. Therefore, it is reasonable to believe that the centrality remains consistent in those years because the increase in refugees is mostly focused on a single country of residence.

    Next, you'll compare the Myanmar data with the Rwandan genocide, which claimed many lives of people of the Tutsi ethnic group in 1994.

  16. On the year filter, click 1994. On the Origin filter, deselect Myanmar and select Rwanda.
  17. On the map card, zoom to Rwanda.

    Persons of concern originating in Rwanda in 1994

  18. On the Migration of persons of concern map, point to the node for Rwanda.

    The outdegree is 31. The summary table indicates there were more refugees than internally displaced persons. The countries with the most persons of concern from Rwanda were the Democratic Republic of the Congo, Tanzania, Burundi, and Uganda. The Total population values for each country are also higher than the number of refugees by hundreds of thousands of people.

    Because there is no data in the Asylum-seekers column of the table, you'll change that column to show different data.

  19. On the summary table card, click the Asylum-seekers header and choose Returned refugees.

    Change the asylum-seekers column to returned refugees.

    The summary table is updated. The total number of returned refugees is over 1.2 million people, meaning that 1.2 million Rwandans had refugee status at some point in 1994 and then returned to Rwanda before the end of the year. The large number of returned refugees is different from what you saw in Myanmar, where the refugees, asylum-seekers, and internally displaced persons accounted for most of the persons of concern.

    One difference between the Rwandan genocide and the examples of mass migration you have looked at so far could be the length of time the conflicts lasted. The genocide in Myanmar and the civil war in Syria are both multiyear conflicts, beginning in 2017 and 2011, respectively, and continuing to the present day. In comparison, the Rwandan genocide took place over an approximately 100-day period from April 1994 to July 1994, meaning the movement of refugees away from their country of origin and movement back to their countries could have happened within the span of a single year.

  20. Use the year filter to repeat the analysis for the years from 1992 to 1995.

    The following table summarizes the data for the specified years:

    YearOutdegree centralityRefugeesReturned refugeesInternally displaced personsTotal population

    1992

    8

    434,731

    140

    0

    434,871

    1993

    21

    450,459

    305

    0

    450,764

    1994

    31

    2,257,570

    1,208,005

    300,000

    3,765,575

    1995

    44

    1,819,367

    240,688

    0

    2,060,055

    Similar to the pattern you observed with Myanmar, the genocide in Rwanda resulted in a drastic increase in the number of refugees in the year of the genocide. The genocide in Rwanda also resulted in an increase in internally displaced persons, while the circumstances in Myanmar did not. The data for Rwanda in 1994 and 1995 also shows the return of persons of concern to Rwanda after the end of the genocide and in the following year. Similar trends cannot be analyzed in Myanmar because the conflict has not yet resolved.

    Another notable difference between Myanmar and Rwanda is the change in centrality. The outdegree in Myanmar remained almost the same from 2015 to 2020, whereas Rwanda saw an increase in outdegree each year, including the year after the 1994 genocide.

Compare changes in movement over time

Your final analysis will compare past and current refugee situations. Ethiopia and Afghanistan both experienced conflicts in the 1980s, 1990s, and 2000s that caused millions of people to become refugees. You'll look at how the movement of refugees from these countries has changed over time.

The Ethiopian Civil War took place from 1974 to 1991. The number of refugees from Ethiopia passed 1 million for the first time in 1979.

  1. On the Origin filter, deselect Rwanda. For Myanmar, click Edit filter.
    Edit filter for Myanmar

    The New filter pane appears.

  2. Search for and deselect Myanmar. Search for and select Ethiopia.
  3. Click Apply.

    The Origin filter updates to show Ethiopia and Rwanda.

  4. Replace the Rwanda filter with Afghanistan.
  5. On the year filter, choose 1979.

    The map card updates to show the migration of persons of concern in 1979. Since neither Ethiopia nor Afghanistan is selected on the Origin filter, all countries of origin are shown.

    Migration of persons of concern in 1979

    The overall patterns on the flow map are easier to see at this point in time than in later years because there are fewer connections between countries. There are also a large number of countries with nodes but no links, especially in western Europe and the Americas. The reason these countries are unconnected is that the countries do not have data for countries of origin. Instead, the origins are listed as Various/Unknown.

  6. On the Origin filter, select Ethiopia.

    The map card updates and zooms in to center on Ethiopia.

    Persons of concern originating in Ethiopia in 1979

    According to the map, the refugees from Ethiopia in 1979 were residing in eastern African and Middle Eastern countries. Although there could have been refugees from Ethiopia living in countries that did not collect data on country of origin, this map shows that Ethiopians in 1979 were seeking refuge in relatively few countries.

  7. Point to the node for Ethiopia.

    The outdegree is 12.

  8. Point to the links to Somalia, Sudan, and Saudi Arabia (the three thickest links).

    The largest number of persons of concern was 1,175,000 in Somalia.

    Link between Ethiopia and Somalia

    Next, you'll look at how the patterns changed over time. The number of refugees from Ethiopia reached a record high in 1980. The Ethiopian Civil War ended in 1991, making 1990 the final full year of conflict. You'll also look at the most recent data in 2020.

  9. Use the year filter to look at the pattern of refugee movements for Ethiopia in 1980, 1990, and 2020.

    The movement in 1980 is mostly the same as 1979, with the exception of Italy, which is the first recorded European country to have refugees from Ethiopia. The outdegree in 1980 was 15.

    By 1990, the countries of residence have changed to include Nigeria, Sweden, the United Kingdom, Italy, Denmark, and the United States, although the outdegree of 14 shows that the countries with Ethiopian refugees has changed, rather than increased. According to the numbers on the summary table, the number of refugees in a single country has also decreased, with approximately 850,000 refugees in Sudan, compared to over 2 million refugees in Somalia in 1980.

    Finally, in 2020, the number of persons of concern from Ethiopia has surpassed 3 million. However, this time the table shows that the majority were internally displaced persons within Ethiopia, and the refugees were spread out across most of the world, with an outdegree increasing to 91.

    Next, you'll look at Afghanistan. You'll start with 1980, the year after the Soviet-Afghan War began.

  10. Change the Year filter to 1980.
  11. On the Origin filter, deselect Ethiopia and select Afghanistan.

    The map card updates to show data for Afghanistan in 1980.

    Persons of concern originating in Afghanistan in 1980

  12. Use the nodes and summary table to find the outdegree and learn more about the persons of concern from Afghanistan.

    There were over 1.7 million refugees from Afghanistan in 1980, with over 1.4 million of them residing in Pakistan, and the outdegree shows that Afghan refugees were residing in only five countries. Like Ethiopia in the early 1980s, most of the Afghan refugees stayed within the Middle East, near their country of origin. Italy is the only country in Europe with known Afghan refugees. Once again, it's important to remember that many countries did not collect data on country of origin at the time.

    Next, you'll look at how the patterns in Afghanistan changed over time. The number of persons of concern from Afghanistan was at a record high in 1991. The War in Afghanistan began in late 2001 and continued until 2021.

  13. Use the year filter to look at the pattern of refugee movements for Afghanistan in 1991, 2002 (the first full year of the War in Afghanistan), and 2020, the same as you did for Ethiopia and Afghanistan in 1980.

    In 1991, the number of refugees from Afghanistan was over 6.3 million. Most of the refugees were residing in Pakistan and Iran, with the rest residing in several countries in the Middle East and Europe, China, and the United States. The outdegree was 12.

    In 2002, most refugees were still living in Pakistan and Iran, but the number of countries with refugees from Afghanistan increased and spread across all continents. This change could be explained by the increase in countries that report countries of origin in their data. The numbers of refugees in countries outside of the Middle East also increased. The outdegree increased to 74.

    In 2020, the number of internally displaced persons in Afghanistan (almost 2.9 million) was larger than the number of refugees (2.6 million). There were also more countries across Europe with a high number of refugees from Afghanistan, and more countries in Africa and South America with Afghan refugees. The outdegree increased to 104.

    Note:

    The War in Afghanistan ended in August 2021, when American troops were withdrawn from the country and the Taliban retook control of the government. Data for 2021 was not available at the time this lesson was published; therefore, the events of August 2021 and their aftermath are not reflected in the data.

  14. Save your workbook.

    Two noticeable trends emerged by looking at the data over time: the increase in internally displaced persons and the increase in outdegree. The high levels of internally displaced persons are consistent with the analysis on Syria and Colombia as well. Therefore, you may want to focus some of your reporting on the current refugee crisis on the context and causes of internally displaced persons.

    The increases in outdegree over time were especially noticeable in Afghanistan, where the outdegree increased with each new year you reviewed. There are a few possible explanations for these changes; for instance, the data collection methodology improved over time, providing more accurate data on country of origin. Other global changes, such as increased use of air travel, could also explain why refugees and asylum-seekers are residing in more countries over time.

In this lesson, you used ArcGIS Insights to explore the global flow of refugees through space and time, fueled by war, genocide, and other destabilizing events. The exploratory analysis you completed can be used to spark further inquiries and analysis into refugee crises and provide a quantified visual to communicate with your audience.

Throughout the lesson, you became familiar with link analysis, which is an analysis technique that allows you to identify and analyze relationships within a dataset using a network of nodes and links. This technique can also be used for analysis in other industries, such as public health or crime analysis.

You can learn more about the refugee crisis with the story In search of refuge.

You can find more lessons in the Learn ArcGIS Lesson Gallery.