Archive for the 'Day in the life of DrugMonkey' category

Today in Reviewer #3: Balanced vs Random Assignment

May 10 2016 Published by under Day in the life of DrugMonkey, Science 101

In my world, when you are about to conduct a between-groups study you do what you can to ensure that there is nothing about the group assignment that might produce a result because of this assignment, rather than your Group treatment.

Let's say we are using the Hedgerow Dash model of BunnyHopping. If you test a population of 16 Bunnies for their speed, you are going to find some are faster and some are slower on a relatively consistent basis. So if you happen to put the 8 fastest ones in the Methamphetamine group and the 8 slowest ones in your Vehicle group, you are potentially going to have an apparent effect of Drug Treatment that is really associated with individual differences in Hedgerow Dash performance.

There are two basic ways to deal with this.

The first is random assignment from a relatively homogeneous pool of subjects. For example, you order all the Bunnies from the vendor in one large group and treat them all identically right up until you assign them to Groups. The idea is that you are unlikely to assign, by chance, Bunnies most likely to produce one particular category of outcome (independent of the treatment) into one Group and those destined for the opposite outcome in another Group.

The second is balanced assignment. For this, you are likely taking your homogeneous pool of Bunnies and testing them on a key variable or two. The individual differences that may potentially produce an apparent result where it doesn't exist can thereby be directly minimized. So perhaps you run a pre-test for assignment purposes. Maybe you use a loud noise as the stimulus instead of Coyote pee, or maybe you've found that Bobcat pee can work. Baddaboom, baddabing, you can rank your Bunnies on Hedgerow Dash speed and assign them to groups such that the starting mean is equivalent.

In my world of behavioral pharmacology, the random assignment approach is the baseline. If you don't at least do this, you had better have a good reason. Doing balanced assignment, I would assert, is generally considered even better. A cleaner and superior design leading to more clearly interpretable outcomes.

I am looking at a reviewer comment on one of our manuscripts with disbelief.

This person appears to think that random assignment would have been "surely" better than the balanced assignment we used. Because, you see, the Reviewer asserts that exposure to Bobcat pee must surely confound the response to Coyote pee. This is despite the fact that this is a repeated measures design in which Bunnies are tested daily for longitudinal changes in Hedgerow Dash performance. With Coyote pee. The Group variable you can think of as the time of day in which they were tested, Bunnies being crepuscular and all. The focus is on this Group variable, not the assay (i.e., longitudinal Dash performance changes). Prior literature has established clearly that there are large individual differences in Dash performance, particularly over time with repeated Coyote pee exposure. The rationale for good balancing of groups is overwhelming. And yet. And yet. This reviewer is certain that random assignment would have been better.

Some days, people. Some days.

3 responses so far

When will the cynicism stop, Doctor?

Apr 04 2016 Published by under Day in the life of DrugMonkey

I am having an increasingly difficult time seeing the fresh faced and excited grad students presenting their posters as anything other than cannon fodder these days.

I do not like this one bit.

I've noticed something else...the one-generation older-than-me folks are looking really beat down.

I do not like this one bit.

34 responses so far

Thought of the Day

It's not ideal for your summary statement to show up whilst at a meeting attended by many of the people on the review panel.

16 responses so far

A message for the Twitteratti

Mar 17 2016 Published by under Day in the life of DrugMonkey

Dudes.

I'm right here. On the blog.

Nothing is (seriously*) wrong with me.

Chill**.

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*i.e., beyond the usual.

**and yes, I am touched by all y'all's concern for my well being. Thank you for that.

24 responses so far

On being ready to go, at all times

Mar 11 2016 Published by under Day in the life of DrugMonkey

You have probably heard that a black protestor being escorted out of a Trump rally was punched by a Trump supporter.

I had a person of a certain visual appearance look at me just a little too long when I walked out of [a public service environment] today.

So I've been wondering.....

What proportion of your life, would you say, requires you to be ready to go when in public?

Now this may be mostly for the men, I don't know. The closest I assume that it comes in most of my female readers' experiences is the threat of a sexual attack in off hours in poorly populated areas.

How often do you think, "I might have to beat the shit out of this fucker right here, right now."?

Or, if you are of a slightly different personality than me, "I need to figure out how I'm getting the fuck out of here without injury, asap".

How often are you the stranger? The other? The person who looks, acts, appears...is assumed to be, the kind of person who some asshole, like these Trump supporters, feels perfectly willing to attack?

A few times ever? That one year you had to move to a new High School?

Occasionally, but mostly when you visit a certain kind of bar? or attend a certain kind of music concert?

Is it a part of you misbegotten early adulthood and you've moved past that?

Or is it a monthly or weekly sensation*, right up to this very day?

How does this affect the way you view the hatred that spews out of the mouth of right wing politicos and their more objectionable supporters?

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*I sat for five minutes wondering if I should make this a main part of the post or let it emerge in the comments. I'm torn. So let's just include it: Does it matter whether you've ever actually had to defend yourself from some jacknut like the Trump fan in the video? Is the frequency of actual attack relevant to how you should feel? or do feel? Is it relevant to how other well-meaning people ("voters") around you should credit your experiences?

24 responses so far

Reminder

You only get high up in gov bureacracy by being an unusually good liar.

Given this, words are of essentially zero value.

Actions are what confirm intent.

One response so far

A comprehensive guide to using social media to your advantage

1. Entertain yourself.

7 responses so far

Thing I am realizing

Feb 17 2016 Published by under Day in the life of DrugMonkey

Being a decent person is fundamentally incompatible with achieving great things or making significant structural change happen.

25 responses so far

Nine

Nine years.

Nine years ago my dismay at the way certain Ecstasy and pot enthusiasts conducted misinformation campaigns online, and dismay over certain realities of the scientific career arc reached a threshold.

I had been reading science blogs and, particularly, several ScienceBlogs, so the outlet immediately presented itself.

Much spleen has been vented and my sanity kept near the critical line.

I've read comments from people that I would have never known, still don't beyond the confines of this blog in many cases* and learned a great deal as a consequence.

I've gotten to know people in my field that I would have known only at a handshake level. I've gotten to know some fantastic people in other fields or walks of life that I would have never run across.

In short, it has been a lot of fun writing this blog over the past nine years.

I can quit anytime I want.
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*as recently as the last few months I've had a long term blog commenter out self to me and I was shocked to discover it wasn't a woman like I thought.

24 responses so far

Papers

January is a great time to look at yourself in the mirror and ask what your plan is for improving your record of publication.

What are your usual hurdles that get in the way? What are the current hurdles?

What works to get you moving?

My biggest problem is me.

We're at the point in my lab where available data are not really the issue, we have many dishes cooking along in parallel at most times. Something is always ready or close to being ready to serve up.

The problem is almost always the wandering of my attention and my energy to kick something over the final step to submission.

The game I have taken to playing with myself is to see how long I can go with at least one manuscript under review. I made it something like 14 mo a few years ago. Of course I then promptly fell into another extended dry spell but....

The other game I play with myself is to see how many manuscripts we can have under review simultaneously. That is, of course, much more subject to the ebb and flow of project maturation and the review process. But if we happen to have a few stacking up, sure I'll use the extra motivation to keep my attention pegged to finishing a draft.

When all else fails there is always "We need this published in order to help get this next grant funded, aiieeeee!"

39 responses so far

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