The Dataset

UM's American's Changing Lives (ACL) survey series is an ongoing, national longitudinal study that covers a wide range of sociological, psychological, mental, and physical health items. I chose this dataset for its depth and breadth, because I wanted to answer a nebulous question: what factors contribute to the onset of depression? Having recently read Johann Hari's book, Lost Connections, I wanted to see if data could back up his claim that depression isn't a biochemical issue, but instead triggered by the isolation caused by social issues, specifically fractured community structure and Western society's increasing conflation of status with purpose.


Descriptive Statistics

After weeks of struggling with R and factor data types, I was able to produce some "descriptive statistics" charts for the midterm. Selections are reproduced below:

Percentage of each wave's active population that responded to feeling depressed "most of the time". Together, this subset comprised of 482 people out of 3617.
More women participated in the study overall, but among the 482 people who reported feeling depressed at any time throughout the study, there was still proportionally more women.
This question surveyed number of years spent in school; a higher percentage of respondents who had no education were also depressed.
My original goal was to see what factors contributed to the onset of depression, so I needed a sample that became depressed later on in the study. Unfortunately, the vast majority of an already small subset of depressed respondents came into the study depressed, but Yoav said that the 75 respondents in Wave 3 were perfectly acceptable.
Within this subset of 75, there was a higher incidence of depression in the 45-54 and 75+ age buckets proportional to the overall active population.
Within this subset of 75, those with lower incomes were also disproportionately depressed. These income brackets were created from figures reported in 1994.

Bootstrapping

After the midterm, I spoke with Yoav about next steps. He introduced me to practice of "bootstrapping", telling me to:

  1. calculate mean scores for relevant categories of survey questions for the 1994 sample for each wave leading up to Wave 3,
  2. calculate the deltas across waves for each category,
  3. repeat this process for 100 randomly selected samples from the overall population, and
  4. compare the results.

The survey questions seemed to be coded pretty consistently, with lower factor levels corresponding to "positive" responses and increasing to "negative" responses. However, the factor levels ranged from 2 to something like 48, so Yoav taught me how to convert them all to the same scale. As for the categories, I chose the following to look at:

  • Activities of Daily Life
  • Paid Employment
  • Reflections on One's Life
  • Self-Description
  • Activities of Daily Life
  • Social Support
  • Voluntary Activity
  • Health and Limitation of Activities
  • Life Events
  • World Views and Religion

With all this prepped, it was time to write some code. Being a R newbie, I didn't know any fancy tricks, so my first stab looked like this:

Unsurprisingly, R didn't like this and chose to act erratically instead... so I took Kaushik up on his offer for R help. After sitting down with him for barely more than an hour, he made more progress than I did the entire semester. Guess which one of us went to art school?

Basically, what he had helped me do was to calculate the mean scores for each category for the 1994 sample, from Wave 1-3, then organized it into a tidy data frame:

So after Kaushik bailed me out of the hell I made for myself, I functionalized what he'd done so that I could apply it 100 more random samples. Being sick and tired of my own ineffectiveness with R at this point, I exported the results to csv's for visualization below:

    Activities of Daily Life

  • About how many times do you talk on the phone with friends, neighbors, or relatives?
  • How often do you get together with friends, neighbors, or relatives and do things like go out together or visit in each other's homes?
  • How often do you attend meetings or programs of groups, clubs, or organizations that you belong to?
  • How often do you typically work in the garden or yard?
  • How often do you engage in active sports or exercise?
  • How often do you take walks?

    Paid Employment

  • Are you self-employed, or do you work for a private employer, or a municipal, county, state, or federal government?
  • Do you supervise others on your job?
  • How much do you enjoy doing that work?
  • How satisfied are you with your job?
  • Aside from the money, are you yourself better off because of your work on this job?
  • Are there other people who are better off because of your work on this job?
  • In addition to your main job, do you have another regular job for which are you paid?
  • How likely is it that during the next couple of years you will involuntarily lose your main job?
  • How much do you agree? I have very little chance to decide how I do my work.
  • How much do you agree? I get to do a variety of different things in my work.
  • How much do you agree? I have a lot to say about what happen in my work.
  • How much do you agree? I am bored with my work.
  • How much do you agree? I am not appreciate for the work I do.

    Reflections on One's Life

  • How satisfied are you with your life as a whole?
  • How much do you agree? My life could be happier than it is now.
  • How much do you agree? These are the best years of my life.
  • How much do you agree? As I look back on my life I am fairly well satisfied.
  • How much do you agree? I would not change my past life even if I could.
  • How much do you agree? Life is not worth living if one cannot contribute to the well-being of other people.
  • How much do you agree? I take a positive attitude toward myself.
  • How much do you agree? At times I think I am no good at all.
  • How much do you agree? All in all, I am inclined to feel that I am a failure.
  • How much do you agree? I can do just about anything I really set my mind to do.
  • How much do you agree? Sometimes I feel that I am being pushed around in life.
  • How much do you agree? There is really no way I can solve the problems I have.

    Self Description

  • During the past week, how often did you feel depressed?
  • During the past week, how often did everything you did feel like an effort?
  • During the past week, how often did you feel that there were people who really understood you?
  • During the past week, how often was your sleep restless?
  • During the past week, how often did you feel happy?
  • During the past week, how often did you feel lonely?
  • During the past week, how often did you feel that no one really knows you well?
  • During the past week, how often did you enjoy life?
  • Have you ever had a time in your life that lasted an entire week or more when you felt sad, blue or depressed most of the time, or when you lost all interest and pleasure in things you usually care about or enjoy?
  • Are you a talkative person?
  • Are you a worrier?
  • Are you the type of person who plans for the future?
  • Have you usually felt pretty sure your life would work out the way you want it to, or have there been times when you haven't been sure about it?

    Social Support

  • Are you currently married, separated, divorced, widowed or have you never been married?
  • How much does your partner make you feel loved and cared for?
  • How much do you feel your partner makes too many demands on you?
  • How much is your partner critical of you or what you do?
  • How much do your children make you feel loved and cared for?
  • At this point in your life, how satisfied are you with being a parent?
  • How happy are you with the way your children have turn out to this point?
  • During the past 12 months, how often did you have contact with your mother, by phone or mail?
  • On the whole, how much do your friend and other relatives make you feel loved and cared for?
  • How much are these friends and relatives willing to listen when you need to talk about your worries or problems?
  • Is there anyone in your life with whom you can really share your very private feelings and concerns?
  • How many of your close family or friends are close to each other in the same way?

    Voluntary Activity

  • Did you do volunteer work in the last year for a church, synagogue or other religious organization?
  • Did you do volunteer work in the last year for a political group or labor union in the last 12 months?
  • About how many hours did you spend on volunteer work during the last 12 months?
  • How much did you enjoy doing that volunteer work?
  • How satisfied were you with the results of your volunteer work?
  • Are you better off because of your volunteer work?
  • Are there other people who are better off because of your volunteer work?
  • Did you do any other things in the last 12 months to help neighbors, friends or relatives who did not live with you?
  • Are you better off because of your help to friends, neighbors, and relatives?
  • Would you have liked to do more of that kind of unpaid work?