Question Description

1. Restate your observation (already done in first assignment). If you wish or feel the need to do so, you can pick a new observation and start over. If you do this, please refer to the first assignment in order to remind you what is required. If you need to revise anything that you, please do so.

2. Restate your three models (already done in first assignment). Many of you may have to come up with new models. Also, if it was stated poorly in the first exercise, fix it now. As always, remember PROCESS. Then make sure you have followed the other rules of thumb: Generality and interesting implications. Also, remember this isn’t a list itemizing different reasons for something, but rather models that are explaining how or why something happens. Ideally, for this assignment, they should be competing models where only one of them can be true. The format should be the same as in the first homework assignment. The first sentence is a simple sentence stating the model. The next couple of sentences can explain how the model relates to the observation. The model should be separate from the observation. Most people have a tendency to state a model too specific to the observation. Watch out for this.

3. State two interesting implications (hypotheses) for each model. Remember to refer to Lave and March for what makes a good model. There are new concepts, also: Simplicity and Fertility. If you are not able to come up with a wide variety of implications and hypotheses, it may be because your model isn’t fertile. Remember the rules of thumb (Generality and Interesting Implications). A few sentences should suffice for each implication.

4. Describe natural experiments that will discriminate between the models. We call any experiment that distinguishes between two models a critical experiment. So, these should be natural experiments that are also critical experiments. (We will refine this more in the next assignment.) There need to be at least two experiments (if it is well done). Three would probably be better. Do not combine this section with section 3 (above). It is a distinct section although many of you will find it repetitive. Depending on your observation and your models, the natural experiments may be very similar to a re-stating of your implications. If this occurs, don’t panic. Likewise, don’t expect or anticipate this to happen.

The following four points are guidelines/requirements.

A) The experiments must be critical experiments. (Refer to Lave and March section 3.2.2.)

B) You must have enough critical experiments to distinguish all of your models from each other. Remember, if an experiment predicts the same result for each model, then it is not a good experiment.

C) All of the experiments must be natural experiments (as defined by Lave and March – and in class).

D) Make sure that you specify which model is supported by a particular experimental outcome. And make sure that for each experiment you discuss more than one outcome.

In addition, you will have to operationalize all of the variables used in the experiments, and you will have to indicate which variables are dependent variables and which variables are independent variables.

Thus, your assignment will look like this:

Section One (old/revised): A description of your observation.

Section Two (old/revised): Stating your first model and explaining how it relates to your observation.

Section Three (new): State the two implications for your first model. Discuss each implication separately. Use two paragraphs, one for each implication.

Section Four (old/revised): Stating your second model and explaining how it relates to your observation.

Section Five (new): State the two implications for your second model. Discuss each implication separately. Use two paragraphs, one for each implication.

Section Six (old/revised): Stating your third model and explaining how it relates to your observation.

Section Seven (new): State the two implications for your third model. Discuss each implication separately. Use two paragraphs, one for each implication.

Section Eight (new): Describe one of your critical experiments. (Remember it has to be a natural experiment as well.) State what the experiment is. State which two models it is distinguishing between. And state what you would expect to see if one of the models is true, and state what you would expect to see if the other model is true.

The description of the first critical experiment should look something like

a) Describe the experiment.

b) State which are the independent and dependent variables.

c) State how you are going to operationalize the variables.

d) Describe the outcomes and state which model each outcome supports

Section Nine (new): Repeat Section Eight with another critical experiment.

Section Ten (new): Repeat yet again with yet another Critical experiment. (Remember, unless you can distinguish all three of you models from each other with only two critical experiments, it is strongly recommended that you use three critical experiments to successfully distinguish all of you models from each other.) Note: If your first experiment distinguishes Models 1 and 3, your other experiments cannot all

distinguish Models 1 and 3 and never discuss Model 2. I assume this is obvious.

You should separate the sections. Do not merely write one long paragraph.

We want to easily see you points.

Realize that we are expecting more at this point. Just because you received nine or ten points on your previous assignment does not mean that you will earn as many points for the same work here.