Tips

Extra Notes & Rules to Know

▪	As a guiding principle remember that MediaLab never looks at your formulas—only the results! How the results of calculated variables occur is completely between you and Excel. Remember that it's your recipe–MediaLab just supplies the ingredients and eats the meal.

▪	You can include as many or as few experimental variables as you like. Feel free to include only those that you need for your calculations.

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A complete discussion of Excel's logic and math functions is way out of the scope if this tutorial. If you've never done calculations in Excel this might seem a bit intimidating at first, but it's really not too bad (honest!). The trick is getting an understanding of how to nest multiple conditions within a single calculation. Grab a pot of coffee and go through Excel's help on this for an hour or so and you'll get it.

▪	To access the relevant help on constructing calculations and conditional statements, press F1 in Excel. Using the Answer Wizard or the Index, look up terms like If, And, Or, Logical Functions, Functions Listed by Category.

▪	When including experiment variables, you can include ANY variable from ANY questionnaire in your experiment—everything goes into responses.xls which is placed in your experiment folder.

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Variable names used for experiment variables need to match the variable names used in the MediaLab data files. This is important to remember for items that record multiple values. For example, let's say you have a multiple response question called MR1 that has five response options. Normally, there won't be a variable in your data file called MR1. Since there are five responses written, they will be called MR1_01, MR1_02, MR1_03 and so forth. This applies also to thought listing items and ranking items. If in doubt, you can always check one of your data files to see how the variable names are written.

▪	When creating conditional statements or calculations based on the value of experiment variables, it will always be the value written to the final data file that will be entered by MediaLab in the value column of Responses.xls.

▪	Essay content can not be accessed as a variable.

▪	Responses.xls should not have any empty rows on the main page

▪	MediaLab executes skips by skipping over items until the desired item is found. This means that if you tell MediaLab to skip to a variable that doesn't exist then the session will end.

▪	Using responses.xls will have no impact on your primary data files—i.e., calculated variables are just for use during the experiment and are saved only in the post-session report (i.e., in the reports folder see above).

▪	In addition to saving a copy of responses.xls under the subject's ID in the data\reports folder, MediaLab will also save a copy as !currentsession.xls in the same folder. This is a temporary file reflecting the responses of the last subject to participate in the experiment.

▪	Currently the MediaLab GoBack function is disabled if calculated skips are involved..