18 Appendix

Here you can find some additional slidesets that provide more details about topics that we address only briefly in the lectures, and a couple of additional resources. They are organized in the same sequence as the module sections.

18.1 Data requirements

18.1.1 Example egocentric study

For a period in the early 2000’s the Demographic and Health Surveys (DHS) survey program collected egocentric sexual network data from representative samples of the population in over 25 countries around the world.

18.1.1.1 Partnership module

This is an example partnership module from the DHS questionnaire. Note there was some variability in the module structure by country over time. Some collected data on the last 3 sexual partners in the last year, some on the last 2 only. Some had information on the date of last sex, some did not. In addition, some countries only included women in their surveys. This complicates the analysis of changes over time and differences between countries.

There was a key omission in all of the versions of the DHS partner module: they did not collect information on the current status of relationships (partnership ended, or partnership ongoing).

The result is that one would need to make assumptions about the current status (i.e., whether the partnership was ongoing) in order to estimate the mean age of ongoing ties. And that is a key parameter needed to parameterize the TERGM for EpiModel.

This omission also influences the estimation of concurrency in these populations. See the paper below for more details:

Morris M, Vu L, Leslie-Cook A, Akom E, Stephen A, Sherard D. Comparing Estimates of Multiple and Concurrent Partnerships Across Population Based Surveys: Implications for Combination HIV Prevention. AIDS Behav. 2014 Apr;18(4):783-790. https://doi.org/10.1007%2Fs10461-013-0618-6

18.1.2 Estimation from egocentric data

18.1.2.1 ERGM terms

Slideset with more details on the estimation process, including population scaling and the principles of scale invariant measures for different types ergm terms.

18.1.2.2 Duration

Slideset with more details on the relationship between dissolution dynamics and relationship duration. Includes a link to an RShiny App for building intuition.

18.2 Model specification

18.2.1 Understanding degeneracy

Slideset with more details on how these degenerate models behave.

18.2.2 Understanding gwesp

Slideset that works through how the decay parameter $\alpha$ influences the value of the gwesp statistic

# Appendix Here you can find some additional slidesets that provide more details about topics that we address only briefly in the lectures, and a couple of additional resources. They are organized in the same sequence as the module sections. ## Data requirements ### Example egocentric study For a period in the early 2000's the Demographic and Health Surveys (DHS) survey program collected egocentric sexual network data from representative samples of the population in over 25 countries around the world. #### Partnership module This is an example partnership module from the DHS questionnaire. Note there was some variability in the module structure by country over time. Some collected data on the last 3 sexual partners in the last year, some on the last 2 only. Some had information on the date of last sex, some did not. In addition, some countries only included women in their surveys. This complicates the analysis of changes over time and differences between countries. ::: resizable <object data="DHSAlbania08.pdf" type="application/pdf"> Unable to display PDF file. <a href="DHSAlbania08.pdf">Download</a> instead. </object> ::: There was a key omission in all of the versions of the DHS partner module: they did not collect information on the current status of relationships (partnership ended, or partnership ongoing). The result is that one would need to make assumptions about the current status (i.e., whether the partnership was ongoing) in order to estimate the mean age of ongoing ties. And that is a key parameter needed to parameterize the TERGM for EpiModel. This omission also influences the estimation of concurrency in these populations. See the paper below for more details: Morris M, Vu L, Leslie-Cook A, Akom E, Stephen A, Sherard D. Comparing Estimates of Multiple and Concurrent Partnerships Across Population Based Surveys: Implications for Combination HIV Prevention. AIDS Behav. 2014 Apr;18(4):783-790. https://doi.org/10.1007%2Fs10461-013-0618-6 ### Estimation from egocentric data #### ERGM terms Slideset with more details on the estimation process, including population scaling and the principles of scale invariant measures for different types ergm terms. ::: resizable <object data="mod3.A1.1-egocentric_estimation.pdf" type="application/pdf"> Unable to display PDF file. <a href="mod3.A1.1-egocentric_estimation.pdf">Download</a> instead. </object> ::: #### Duration Slideset with more details on the relationship between dissolution dynamics and relationship duration. Includes a link to an [RShiny App](https://sgoodreau.shinyapps.io/ageextantties/) for building intuition. ::: resizable <object data="mod3.A1.2-relDur.pdf" type="application/pdf"> Unable to display PDF file. <a href="mod3.A1.2-relDur.pdf">Download</a> instead. </object> ::: ## Model specification ### Understanding degeneracy Slideset with more details on how these degenerate models behave. ::: resizable <object data="mod3.A2.1-degeneracy.pdf" type="application/pdf"> Unable to display PDF file. <a href="mod3.A2.1-degeneracy.pdf">Download</a> instead. </object> ::: ### Understanding gwesp Slideset that works through how the decay parameter $\alpha$ influences the value of the gwesp statistic ::: resizable <object data="mod3.A2.2-gwesp.pdf" type="application/pdf"> Unable to display PDF file. <a href="mod3.A2.2-gwesp.pdf">Download</a> instead. </object> :::