I See Dependent and Independent Variables

I see dependent and independent variables all day long. Years of study both at the undergraduate and graduate level combined with many more years teaching experimental psychology and research methods have worked their effect on me.

The other day, I was driving to Texarkana and saw cattle egrets along the way. In one field with cattle, there were many more egrets than in other fields. That observation started me wondering why that one field had so many more egrets than the others.

Were I to follow up on my observation, then the number of cattle egrets in each field would become a dependent variable in my research.

A few days later, I was walking around campus and I noticed that some parked cars had one current campus parking permit affixed to their rear windows. However, other cars had two or more parking stickers affixed. Now, an independent variable came to mind: the number of parking stickers on each window. In other words, I could now use those two groups to divide drivers into two naturally-occurring groups.

Very quickly, hypotheses began to form in my mind. Were the drivers with more stickers students who were illustrating their tenure on campus? Or, were they simply unable to easily remove the old stickers?

After being exposed to research methods classes and after designing and conducting research projects, the world takes on a new look. Dependent and independent variables pop out everywhere.

Confused about the difference between dependent and independent variables? I like to find the dependent variables in a study first. The dependent variables are the measurements in research. Also, all of the participants will be measured.

On the other hand, independent variables divide the research into groups. The groups can occur naturally or be operationally defined by the researcher. The levels of the independent variable will not be the same for all participants. In the example above, some drivers have one parking sticker while others have two or more. See?

Care and Feeding of Editors

A recent column by Lynn Worsham in the Chronicle of Higher Education (September 8, 2008) discusses what academic journal editors look for in submissions to their journals.

She identifies several oft-made mistakes by authors:

• submitting the wrong type of article to a journal
• failing to proofread the submission for grammatical and careless errors
  
• citing sources incorrectly
• being unaware of previous similar research in the same journal and not citing it
• not following specific submission requirements (e.g., # of copies or no return envelope)
• submitting a conference presentation without rewriting it as a paper
• arguing with editor over rejected submissions

Other suggestions included knowing the appropriate style manual followed by a particular journal, following the journal's rules exactly, and realizing that rejection was a fact of academic life.

In our chapter 12, we cover some of the steps necessary to take a research project to completion. Finishing a research project can mean more than one thing. It could mean presenting your results orally in class or in public. Ultimately, it could mean publishing your research in a peer reviewed journal. If that's your goal, pay attention to Worsham's suggestions.

Crows Recognize People? Dogs Recognize Cars?

I have a fondness for field research. John Marzluff of the University of Washington and his colleagues observed that the crows they had trapped previously in order to band them for identification seemed to be harder to catch later.

So, they decided to test that hypothesis by conducting a field experiment. Three researchers, Marzluff and two students, then wore a caveman mask and trapped and released seven crows. Later, whenever one of the three wore the map on campus, the crows scolded them severely.

However, whenever they walked on campus wearing another mask (a Dick Cheney mask), the crows ignored the wearers. This, of course, was the control condition.

It seems, thus, that crows recognize people who catch and handle them and remember them later. Other researchers, too, have seen similar behaviors in crows and related birds. See a New York Times article for more information.

Informally, I have conducted similar exercises. I like to watch my dogs when I pull up in a rental car. Invariably, they bark at me viciously from behind the living room windows. They stop barking after I exit the rental car and start to walk toward the front door. Also, I have often sat outside in the afternoon while the dogs walk around in the front yard. I watch carefully for cars while I wait. I don't want to explain to my children why their dogs were run over. Interestingly, when I see my wife a block away and go to protect the dogs, they hear her van approaching and start to run in its direction (something they do not do for other vehicles).

So, it seems that dogs and birds can recognize and remember things about us.