Pacifiers and baby boys

I'm a bit behind on this one, but this study was too interesting to pass up.

Apparently, research suggests that pacifier use by boys limits their social development.

So we'll start with the bias alert.  I have a baby boy, and he does use a pacifier to help him go to sleep.  I didn't have any particular feelings about this, I just gave it a whirl and liked the way it helped him calm down when he was tired.  Give it 5 minutes, and he tends to spit it out and go to sleep.  That seemed rational to me, I actually was unaware there was much controversy about this until I got reading this article (reiterating Dubbahdee's point that I should never read parenting advice on the internet....oops).

Obviously, I don't yet know what his social development is going to turn out like (though at the moment he's astoundingly unsympathetic to my lack of sleep), but I generally hope it's okay.   End bias alert.

It took me a while to find the actual paper (why oh why do so many news sources not link to the actual paper????), but after scanning the whole thing I had a couple thoughts.

The headlines about this paper were stupid, of course.  The author actually had a pretty good theory based on actual science (babies learn emotions in part through mimicry, she wondered if a pacifier would make this harder for babies because their facial muscles were occupied), and of course it got over reported. Most headlines just mentioned "pacifier use" in general, but she clarifies pretty quickly that they only studied pacifier use during baby wake time....specifically excluding the type of pacifier use I described above (as a sleep aid).  This makes sense (the woman does have 3 boys herself after all) because you don't have to spend very long around babies before you realize they're probably not learning much when they're trying to fall asleep.  They're mostly just crying.

Anyway, the set up for the study was pretty good.  They assessed both 6 and 7 year olds and their emotional reactions vs pacifier use, and then later college students who were questioned about their history of pacifier usage to tie it to adult development.

For that second, I was curious about the length of pacifier use we were talking about, as this was based on the recollection of college students and their parents, and I was wondering how accurate that would be.  This graph sums it up nicely:

I'm not familiar with the emotional intelligence scale they're using, so I'll take their word for it that 4.7 to 4.4 is statistically significant....but wow, daytime use of a pacifier until 5 years of age?  That does seem like it should cause some concern.  Also, it seems as those the recollection bias here would be clustered at either end.  Parents would remember more accurately either remarkably short or remarkably long pacifier use...but that's just a guess.

Overall, I thought it was annoying that "daytime use of pacifiers until kindergarten" got labeled as just "pacifier use", but I thought the research was certainly intriguing.  I especially liked that they tested both younger children and adults to help prove their theory, as emotional development is most definitely a complex process that takes decades to work through.

What I actually liked about this study the most was Ann Althouse's take on it.  She wondered if this meant you could stop overly emotional women from being overly emotional by giving them Botox so they couldn't mimic those around them.  I'd say it's worth a shot.

Now THAT's how you write a science headline

"Babies Shun Altruism, Prefer Bouncing"

Speaking of replication of results, this study failed to substantiate the idea that 10 month old babies had a moral code.  Turns out that the their preference for "helpful" robots was based less on the fact that the robots were helpful, and more on the fact that they bounced.

I'm sort of curious how many of the original study authors were parents.  I've only been a mom for 19 days and even I could tell you that babies like bouncy things more than discussions about man's existential angst.  The 2 AM feeding helps you figure these things out pretty quickly.

For fun, I decided to conduct my own n=1 experiment and to present my son with a survey regarding his preference for robots in general and their morals in particular.  I thought it was a fairly well crafted survey.

I think my findings are best summarized with this picture:

I think that should be good enough for any number of social psychology journals.  

Rich Mom Poor Mom

I have a sleeping baby in my lap, so you'll forgive me if I have a one track mind.

Yesterday we met with a nurse who let us know that in Sweden, they have now set minimums for skin to skin contact between mom and babies during hospital stays.  If you don't do the minimum, you pay the hospital bill.  This morning, in my first perusal around the internet in a few days, I see that Mayor Bloomberg is trying to find ways of encouraging new mother's to breastfeed.

A note on research regarding babies and various practices in infancy:  Babies are a lot of work.  I realize I'm preaching to the choir on this, as many of my readers have successfully raised quite a few children, but it's true.  Many of the practices that show lots of benefits for babies (skin to skin contact, breastfeeding, etc) take even more time than the alternatives.  While I believe these things are good for babies on their own, all data collected on these practices will be complicated by the fact that parents who engage in them tend to have more time, resources, and support than those who don't.  Pushing these practices on those who are already particularly stressed may not have as profound an outcome as it did in the study, as the groups went from self selecting to random.

Something to think about for the policy makers.

Sorry, I've been reading over a lot of hospital literature and getting mildly annoyed.  I think that means the pain medication has worn off.  Nurse!

Spanking and Mental Trauma

The headline reads "Spanking Linked to Mental Illness", and I was immediately intrigued.  Spanking, generally, is a very hard thing to study, as it is so often correlated with other things.  Physical punishment of children is often linked to frustrated and under resourced parents, cultural norms that can be positive or negative, and even immigration status.

Curious how the study authors controlled for such things, but assured by the article that they had, I flipped over to the study itself.  It didn't take long for me to realize this was yet another example of bad journalism mucking about with a half decent study.

The article starts like this:

Although the American Academy of Pediatrics (AAP) strongly discourages spanking, at leasthalf of parents admit to physically punishing their children. Some research suggests that as many as 70-90 percent of mothers have resorted to spanking at one time or another. Anew study published in the journal Pediatrics may cause parents to think more carefully before laying a hand on their little ones.

However, the study states:

Physical punishment was assessed with the question, “As a child how often were you ever pushed, grabbed, shoved, slapped or hit by your parents or any adult living in your house?” Respondents who reported an answer of“sometimes” or greater to this event were considered as having experienced harsh physical punishment. The term harsh physical punishment was used for this study because the measure includes acts of physical force beyond slapping, which some may consider more severe than “customary” physical punishment (ie, spanking).

 So the study specifically excluded "customary" physical punishment when it assessed the effects on future mental illness....which pretty much completely contradicts the headline.   I also doubt this is what 70-90% of mother's are admitting to when they spank "at one time or another".  

Irresponsible.

It's all (culturally) relative

Last week I put up a post regarding a study on sexism levels in men whose wives stay at home.  I argued that due to the diversity of that group of men, and the variety of reasons a woman might stay home, this study was essentially meaningless.

Another issue came up in the comments section that I wanted to touch on: cultural relevance of data.

Most studies that get press here in the US are from the US, performed on American subjects.  This is sketchy business.

In the study about stay at home moms, mothers who worked part time were lumped in with the stay at home mothers.  Interestingly, in the Netherlands, this would actually be 90% of the women.  Does that mean that nearly every Dutch man married to a woman is more likely to be sexist?  Or does it mean that part time work has different value in different cultures?

I took a look around for some other examples, and found that in China, many women see working as part of a new found freedom.  At a conference I attended a few months ago, I talked to a man from Shanghai who mentioned that his wife went back to work because she couldn't have handled trying to fight off the two grandmother's, both of whom wanted to watch the child.  Due to the one child policy, this was the only chance they would get to have a grandbaby.  In many ways, it was actually the hierarchical/patriarchal culture there that pushed his wife to go back to work, as opposed to having her stay home.  

As the world continues to flatten out, and as America continues to welcome new immigrants, we must be conscious of who studies are actually looking at and how generalizable the results are.  In the sexism study, even the authors admitted their findings were meant to be a commentary on the US only....but it should raise some questions that they seemed to be chasing after a structure that doesn't exist in some very liberal countries.

Something to consider, depending on the goal of the study.

Researching New Family Structures...Cutting Through Politics with Facts

I've been reading Bad Science by Ben Goldacre, and I highly recommend it.

In it, he quotes an interesting study regarding how likely people are to pick apart studies that challenge their preconceived notions.  Unsurprisingly, people are far more likely to notice flaws in studies they don't agree with than those they do.  He then made a somewhat tongue in cheek suggestion that perhaps all papers should have to list the method section first, to make sure that it was assessed before you knew what the conclusion was.

That came to mind today when I was reading Mark Regnerus's explanation of his new research in to new family structures.

I was unsure what to think of this study just from the headline.  I've actually read some of Regnerus's research in the past and disliked it, so I wasn't sure what I'd think of his take on this issue.

I found the paper fascinating.

Part of his premise started from his observation that adoption presents a unique challenge for parents, as is well acknowledged by research.  Thus, it interested him that many studies on gay and lesbian parenting showed no differences between that and heterosexual couples.  That appealed to my data analysis side, it's certainly not an observation I would have put together right away.  The study was focused on the young adult (18 to 39) population, and thus the slightly longer term outcomes of products of these families.

What impressed me so much about this study was how many pains they took to correct methodological errors in previous studies.  With such a highly politically charged topic, it would have been easy for him to just shy away from this study.  While critics were quick to point out that his funding came from two conservative organizations, his conclusions are not necessarily conservative.  While he does find that the outcomes for children of gay parents have worse outcomes on most metrics*, he acknowledge the high level of broken homes from these parents as a huge contributing factor.  His population makes the study a bit retrospective, and he acknowledges these limitations.  From his Slate.com article:

Let me be clear: I’m not claiming that sexual orientation is at fault here, or that I know about kids who are presently being raised by gay or lesbian parents. Their parents may be forging more stable relationships in an era that is more accepting and supportive of gay and lesbian couples. But that is not the case among the previous generation, and thus social scientists, parents, and advocates would do well from here forward to avoid simply assuming the kids are all right.

 William Saletan (and others) have quickly responded with the idea that this study actually supports the need for gay marriage by proving that the broken homes of the past were damaging to children.  Clearly Regenrus does not rule that out in his study....he is quite clear that he knows the selected age group covers only those children born 1971 to 1994 (pre legal gay marriage), and he goes very in depth with the broken homes angle.....acknowledging that many of the broken homes were fractured hetero marriages that preceded the same gender relationships.

The value of a study like this however, is not merely in the conclusions.  The value is that it unsettles the debate, and hopefully precipitates a response from those who disagree with him.  In emotionally and politically charged fields, the response to data should be newer and better data that corrects the perceived problems in the last study.  Politics should not be a reason to consider something "settled", and we need researchers who are at least willing to entertain the other side, if only to give people something to respond to.

I know most people will not make up their mind on this issue because of a research study, but I don't think that's a reason to not do research. Whatever a person believes, I would hope this study could be read with unbiased eyes, methods first....just to see what you think.

*As I commented in this post metrics on child rearing can be hard to determine.  Some of the ones used in this study were: being unemployed, less healthy, more depressed, more likely to have cheated on a spouse or partner, smoke more pot, had trouble with the law, report more male and female sex partners, more sexual victimization, and were more likely to reflect negatively on their childhood family life.  The full list is in the paper here.

Sexism and stay at home moms

I was just thinking I wanted to find a good marriage and family research paper to sink my teeth in to.

This one came across my inbox today, and I didn't have to get much further than the abstract before I knew it was going to be a doozy.  Read for yourself:

In this article, we examine a heretofore neglected pocket of resistance to the gender revolution in the workplace: married male employees who have stay-at-home wives. We develop and empirically test the theoretical argument suggesting that such organizational members, compared to male employees in modern marriages, are more likely to exhibit attitudes, beliefs, and behaviors that are harmful to women in the workplace.

*Bias Alert*
My mother was a stay at home mom.  Therefore my father would have qualified for this study, and it is hard for me to even read their hypothesis without remembering that.  I happen to credit my father with giving me my passion for statistics and data analysis, and he has never once discouraged me from doing anything I wanted to professionally (with the exception of when I mentioned law school....that he soundly discouraged as a waste of talent....and this was  15 years before anyone was talking about a law school bubble).  I will not go in to all the details of my parents marriage here, but I doubt you could find anyone who would call my parents marriage anything less than an equal partnership focused on doing what was best for the family.

As an extra level of bias, I will be continuing my (full-time) job post baby.
*End Alert*

I've noticed a disturbing trend in both the general population and academic research: people seem to get very hung up on conflating "stay at home mom" with "traditional marriage".  The study authors do this openly....they admit that they classify a marriage as "modern" based solely on whether or not the wife works full time.  The only criteria for "traditional" is that she doesn't work at all, and part time work is all classified as "neo-traditional".

To ignore the economic realities that drive families to make decisions about work seems to me to be an immense oversight.  I have met plenty of stay at home mothers who were in very equitable marriages, and I have met quite a few working mothers whose primary source of stress was their husbands continued expectation that they were still responsible for all child care/household duties.  I believe that using only one metric to rank a marriage as "traditional" or "modern" is a horrible over generalization....especially since most women with small children would prefer to work part time.  In fact (from the Pew study):

The public is skeptical about full-time working moms. Just 14% of men and 10% of women say that a full-time job is the “ideal” situation for a woman who has a young child. A plurality of the public (44%) say a part-time job is ideal for such a mother, while a sizable minority (38%) say the ideal situation is for her not to work outside the home at all.

So 90% of women don't think the "modern" setup is ideal when there are young children involved.  If one of these women than chooses to stay home with her kids, has her husband truly regressed from "modern" to "traditional"?

For both the economic reasons and the "women's choice" reasons, I reject studies that try to tie stay at home motherhood to anything else.  The sample is just too broad, and the reasons too varied.  It also undermines exactly how expensive child care can be....by my estimate, my mom would have had to bring home at least $4000 a month (in today's dollars)  to pay for child care for 4 children.  $4000 after tax is a pretty hefty before tax salary.

I don't argue that personal life can affect professional attitudes, and I would never advocate for sexism in the workplace.  In this study however, I really had to question the motives.  Is it really the best idea to fight gender stereotypes with stereotypes about very broad choices?  Is the point here that the workplace will only be fair when women participate as much as men?  Isn't it a bit sexist to totally disregard the role women play in the decision to work or not work?  Shouldn't we all just be able to do what's best for our families, no questions asked?

Outcome metrics and the research we do not do

I've spent most of last week at work trying to perfect a grant proposal that pretty much everyone in our program has to sign off on.  On Thursday, Friday and today there was a great deal of discussion about what metrics we could use to measure our outcomes, should we get funding.

It's actually not an easy question, as the project we're working on is a general good thing (patient education) designed to address a multitude of issues, as opposed to something more targeted.

Watching half a dozen people go back and forth about all this got me thinking about how often it is taken for granted that somewhere out there is a definition for "success" in various topics.

When I took a child development class in grad school, I remember in one of the first classes someone asked what the best parenting methods were.  Our professor replied that there really couldn't be a consensus, because no one could agree on what would qualify as a success.  He proceeded to use religion as an example:  for parents of strong religious persuasion, a child who grew up a financially successful atheist would not necessarily be what they were going for.  Conversely, secular atheist parents might be distressed at a strong religious conversion.

There are probably scores of good studies that could have been done on parenting methods if we actually had a definition of success we could all agree on.  Too frequently, I think people overlook this point.  The reason so many strange fads in parenting can get going is because it is really really hard to prove anyone right or wrong.  Even if you try, you might just wind up with the dodo bird verdict.

If you can't agree on where you're going, you most certainly can't tell people how to get there.  The studies you don't do are often as important as the studies you do.

Correlation and Causation: the Teen Pregnancy Edition

One of the first posts I ever did was on correlation and causation.  In it, I spelled out the three rules to consider whenever two variables (x and y) are linked:

1. X is causing Y
2. Y is causing X
3. Something else is causing both X and Y

While most people jump to the conclusion that it's number 1, Matthew Yglesias wrote a piece for Slate.com this week where he rather awkwardly jumps to conclusion number 2.  

He starts off well with the second paragraph, but then goes to very strange place in the third: 

Delivering the commencement address last weekend at the evangelical Liberty University, Mitt Romney naturally stuck primarily to “family values” and religious themes. He did, however, make one economic observation that intersects with some fascinating new research. “For those who graduate from high school, get a full-time job, and marry before they have their first child,” he said, “the probability that they will be poor is 2 percent. But if [all] those things are absent, 76 percent will be poor.”
These are striking numbers, but they raise the age-old question of correlation and causation. Does this mean that the representative high-school dropout would be doing much better had he stuck it out in school for a few more years? Or is it instead the case that the population of high-school dropouts is disproportionately composed of people who have attributes that lead to low earnings?
When it comes to early pregnancy, surprising new evidence indicates that Romney and most everyone else have it backward: Having a baby early does not hamper a young woman’s economic prospects, as Romney implies. Rather, young women choose to become mothers because their economic outlook is so objectively bleak.

Say what?

As a former teenage girl myself, this is a strange conclusion....I certainly never met a teen mom who would have put it that way.  But surely there was some wonderful evidence to support this scathing conclusion?

Well, not really.  Here's the original paper....and  here's how the authors conveyed their thoughts:

We describe some recent analysis indicating that the combination of being poor and living in a more unequal (and less mobile) location, like the United States, leads young women to choose early, non-marital childbearing at elevated rates, potentially because of their lower expectations of future economic success. ...These findings lead us to conclude that the high rate of teen childbearing in the United States matters mostly because it is a marker of larger, underlying social problems.

The emphasis was mine....but notice how much more careful they are in their language.  If you take my list above, you see that they are challenging possibility number 1, seeing if #2 is a feasible conclusion, but ultimately pointing the finger at #3....i.e. "larger, underlying social problems".

For example, the cite low maternal education as a risk factor for teen pregnancy...which one could presume could be either the result of or the cause of low income.

Teen pregnancy is complicated, and honestly I would be very surprised if you could ever figure out a way to pin it on just one factor.  Additionally, so much information is unavailable that it can be hard to parse through what you have left.  A key factor in all of this would be to determine if higher income girls weren't having babies because they weren't getting pregnant or because they were having abortions....data which could lead to very different conclusions.

I fully support this study, by the way, questioning the prevailing wisdom is always a good thing. What I resent is when people think just by flipping the order of a normal conclusion that they're being clever.

X could cause Y, Y could cause X, something else could be causing both.

Then again, it could also just be a coincidence.  

Why most marriage statistics are completely skewed

Apparently Slate.com is now doing a "map of the week".  This week, it was a map of states by marriage rate.  Can't get it to format well....click on the map and drag to see other states.

It shows Nevada as the overwhelming winner, with Hawaii second.  This reminded me about my annoyance at most marriage data.

Marriage data is often quoted, but fairly poorly understood.  The top two states in the map above should tip you off as to the major problem with marriage data derived from the CDC in particular....it's based on the state that issued the marriage license, not the state where the couple resides.  Since all (heterosexual) marriages affirmed by one state are currently recognized by every other state, state of residence information is not reported to the CDC.  This means that states with destination wedding type locations (Las Vegas anyone?) skew high, and all others are presumably a bit lower than they should be.  Anecdotally, it's also conceivable that states with large meccas for young people (New York City, Boston, DC) may be artificially low because many young people return to their childhood home states to marry.  This

The other problem with marriage data is the resulting divorce data is even more skewed.  Quite a few states don't report divorce statistics at all (California, Georgia, Hawaii, Indiana, Louisiana, Minnesota) and the statistics from the remaining states are often misinterpreted.  One of the most commonly quoted statistics is that "50% of marriages end in divorce".  This isn't true.

In any given year, there are about twice as many marriages as there are divorces....but thanks to changing population, changing marriage rates, people with multiple divorces, and the pool of the already married, this does not mean that half of all marriages end in divorce.  In fact, if you change the stat to "percent of people who have been married and divorced", you wind up at only about 33%.  More explanation here.

Ultimately, when considering any marriage data, it is important to remember that there are no national databases for this stuff.  All data has to come from somewhere, and if the source is spotty, the conclusions drawn from the data will likely be wrong.  This all applies to quite a few types of data....but marriage data is used with such confidence that it's tough to remember how terrible the sources are.  A few people have let me know that I've ruined infographics for them forever, and I'm hoping to do the same with all marriage data.

You're welcome.

THE KIND OF DATA I ABSOLUTELY HATE

Hate's a strong word.  I get that.  I also get that data and survey types are not always the sort of thing that inspires people to strong hatred, but here we are.

In this post I mentioned my annoyance at perception/prediction polls.  The one I referenced was based on women who didn't change their last names and their level of marital commitment.  Commenter Assistant Village Idiot mentioned another example, which I also liked ""Do you think earthquakes are more likely now because of climate change?" What we think has nothing to do with anything. The earthquakes will happen according to their own rules."  

In writing that post however, I forgot to mention that same study included an even worse piece of data.  As a rebuttal to the "Midwestern college kids don't think non-name changing women are committed" they included a remark that women who didn't plan on changing their names didn't feel less committed. 


I HATE STATEMENTS LIKE THAT.

I would really love it if someone could tell me if there's a proper name for this sort of thing, but I always think of it as "the embarrassing question debacle".  Basically, researchers ask people questions with a potentially embarrassing answer, and then report it as meaningful when people do not answer embarrassingly.

There are only two types of people I have ever heard who will admit they went in to their marriages less than completely committed:

1. Those who have been married successfully for quite some time who are now comfortable in admitting they were totally naive when they walked down the aisle.
2. Those who are already divorced and reflecting on what went wrong.

Level of commitment is best assessed in retrospect, and I look with great skepticism at anyone who says they can gauge it before the fact.  

Getting at the reasons people do things can be brutal.  Your only source for your data also has the biggest motivation to conceal it from you.  Some people are actually doing things for good reasons, some just want to look like they are, and some are lying to themselves.  Unless a study at least attempts to account for all 3 scenarios, I would hold all answers suspect.

Correlation and Causation: the Housework Edition

After yesterday's comic, I was hoping to find a good example of a news story where they equated correlation and causation.  In case you're curious, it took me under 5 minutes.

Headline: Why Being Less of a Control Freak May Make You Happier

To start, let me just mention that correlation implies that two things are moving together....as one goes up, so does the other.  Alternatively, as one goes up, the other goes down, or vice versa.  Either way, their outcomes appear to be tied.

Causation on the other hand, says that one thing is causing another.  What yesterday's post was referring to is the often made mistake that just because two things are correlated, we can infer that one is causing the other.  This is not always true, and believing so may get you drawn as a stick figure.  

Anyway, the article above illustrates that point nicely.  The author set out to find out if being a control freak mom made people unhappy....and low and behold it appears to.  55% of women who said they delegate to a partner or spouse at least once a week reported themselves as "very satisfied" with their life.  For those who did not delegate that often, the number was 43%.  

Now, I'll mostly skip the use of the word "delegate" in this article, though it does bother me.  My husband does plenty around the house, but we mostly just consider that "teamwork" not "delegating".  I don't start the week handing out tasks to him, and he doesn't consider the work he does around the house a favor to me.  It's just what needs to get done.

More importantly however, is the articles conclusion that delegating will make people happier.  While delegating and happiness are perhaps correlated, they are not necessarily causal.  It's possible that the women who don't delegate do so because their spouse is lazy, hostile, or generally not involved....all things which would also make them less happy over all.  It's also possible that women who don't delegate are controlling, martyr's, passive aggressive, etc, and that makes them unhappy too.

I had a great stats professor once who opened every class with this:

"If you get one thing out of this class, let it be this:

When x and y or correlated, you have 3 possibilities:

1. X is causing Y
2. Y is causing X
3. Something else is causing both X and Y "

Lack of delegating could cause unhappiness.

Unhappiness could cause people to stop delegating.

Something else entirely could cause people to not delegate and to be unhappy.

When in Doubt, Blame the Journalist

Within minutes of hitting "publish post" on my mission statement, I found an article that reminded me of one of my worst pet peeves when it comes to data/science/studies of all types.  The headline read  "Keeping Your Name? Midwesterners Are Judging You".  My ears (eyes?) perked up at this headline, as I am among those women who declined to change her name post-nuptial.  Despite knowing that Jezebel is not often the best place for unbiased reporting, I gave it a read.  

The article linked to a much more well nuanced article here, but the basics are as follows: students at a small midwestern college feel that women who don't change their last names when they get married are less committed to their relationships than those who do.  This was interesting in part because the number of people who felt negatively about this quadrupled between 1990 and 2006.  

For the personal reasons listed above, I find this interesting.  However, when you look at the numbers (2.7% of 256 and 10.1% of 246 which Jezebel did include) and do a little math, you realize that this "jump" is a difference of 18 people.  

A few things to consider about this:

1. I couldn't find that this was published anywhere.  It seemed to be a sort of "FYI for the headlines".
2. Apparently there's no data on whether or not this perception is true.  My bias would be that it's not, but I couldn't find data actually saying if the perception was correct.  This happens in many "perception" studies....they quote percentages who believe something with the implication that a certain belief is wrong without ever proving it.
3. There wasn't a gender breakdown of who those 18 people were.  If most were female, then isn't their perception likely to be based on experience?  As in "well if I didn't do it, it would be because I wasn't committed"?  That not judgement of others, that's judgement of self.
4. Have any of their professors (or TV shows, or other media sources) recently made disparaging remarks about this?  18 people who all very well might know each other (the university surveyed was under 1000 students) could easily be influenced in their answer  by even one strong source.
5. As college students, presumably very few of those polled were actually married.  From my experience in college, I would conjecture that this is a phase of life during which people are very idealistic regarding their future mates without having many real experiences to back it up.  I put much more stock in what people who are actually married use to feel out level of commitment than what someone who's never walked down that aisle thinks.

All that being said, it looked like the study authors were careful to address several of these points (especially the "this is not a representative sample" point.  It was only in the translation that conclusions were drawn that were more dubious.  

Scientists have very little incentive to exaggerate the meaning of their findings.  They are in a profession where that could be very damaging.  Reporters for both old and new media have EVERY incentive to spin things in to good headlines.  Remember that.