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Tip: Read the chapters [[php|Introduction to PHP]] and [[array|Introduction to Arrays]] for a better understanding of the complex example codes shown below. | Tip: Read the chapters [[php|Introduction to PHP]] and [[array|Introduction to Arrays]] for a better understanding of the complex example codes shown below. | ||
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+ | ===== General Usage ===== | ||
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+ | The experimental logic (between-subject) assumes that the participants of an experiment are divided into experimental groups. Depending on the group assignment, a question, text, image or video (the treatment or stimulus) is then varied. | ||
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+ | Even if your goal " | ||
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+ | ==== Step 1: Assignment to experimental groups ==== | ||
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+ | Create a question of type [[: | ||
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+ | < | ||
+ | Control Group | ||
+ | Positive Exemplars | ||
+ | Negative Exemplars | ||
+ | </ | ||
+ | |||
+ | After saving, SoSci Survey adds a numeric code for each group, e.g. | ||
+ | |||
+ | < | ||
+ | 1 = Control Group | ||
+ | 2 = Positive Exemplars | ||
+ | 3 = Negative Exemplars | ||
+ | </ | ||
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+ | With the //Type of drawing// you can decide whether you want to select "Equal distribution in completed questionnaires" | ||
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+ | For //Codes drawn per interview// leave the value 1. Thus, the participant is only assigned to one of the experimental conditions/ | ||
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+ | ==== Step 2: Presentation of the Stimulus ==== | ||
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+ | In **Combine Questionnaire**, | ||
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+ | The random generator will now randomly draw one of the defined groups and store its code in a variable with the random generator' | ||
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+ | Place an element " | ||
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+ | If the stimulus is a question (i.e. in group A another question from the **List of Questions** is to be displayed than in group B), the function '' | ||
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+ | The following PHP code would display the question " | ||
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+ | <code php> | ||
+ | if (value(' | ||
+ | question(' | ||
+ | } elseif (value(' | ||
+ | question(' | ||
+ | } else { | ||
+ | // You may omit the else part, | ||
+ | // nothing happens here | ||
+ | } | ||
+ | </ | ||
+ | |||
+ | The function '' | ||
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+ | The other sections of this manual explain various areas of application of randomization. | ||
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===== Drawing of a Random Number ===== | ===== Drawing of a Random Number ===== |