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Method

Subjects

Research subjects were 126 white airmen who had recently finished basic training and were stationed at Lowry Air Force Base.

Experimental Task

The cooperative task providing the context for the present experiment was a management- training activity called the railroad game. This activity involved operation of a railroad business which received orders to ship a variety of cargo among 10 cities in cars of 6 different types. Since the various types of cargo required different types of cars, effective operation depended upon the availability of appropriate cars in the proper cities in order to fill each order. The three participants filled shipping orders; kept records on profits, losses, maintenance and shipping charges, fines and the location of all railroad cars; and informed the railway central office of each financial transaction over an intercom (the experimenter served as "station master"). The effectiveness of the business increased as the participants learned (a) that some cities shipped only certain types of products and therefore required only certain types of railroad cars, (b) that sufficient numbers of cars had to be maintained where they were likely to be needed, and (c) that money could be saved by shipping products in cars that would be needed at the station of destination. The business was conducted during a series of five 15 minute sessions called workdays. [...]

Independent Variables

The three independent variables in the experiment were (a) type of help (voluntary vs. directed vs. observed helping), (b) group outcome (success vs. failure vs. ambiguous outcomes), and (c) race of the less competent group member (black vs. white). Subjects were assigned randomly to one of the 18 cells in a 3 x 3 x 2 factorial design [...]

There were three conditions of the type of help variable: In the voluntary helping condition, the subject was induced to help the less competently performing groupmate in such a manner that the subject would feel that his help was voluntarily extended [...]

In the directed helping condition, the subject was induced to help the less competent groupmate in such a manner that the subject would feel that his help was extended as a consequence of instructions to do so. [...]

In the observed helping condition, the subject observed another group member (the second confederate) voluntarily help the less competent group member.[...]

There were also three conditions of the group outcome arable: In the success condition, subjects were told that the group would be considered successful or “win” the railroad game if their profits surpassed the average obtained by groups of Air Force officers. [...]

In the failure condition, subjects were told that the group would be competing against the average earnings by groups of Army privates just out of basic training [...]

In the ambiguous condition, subjects were told that the experimenter ordinarily compared their performance to that of similar groups who had participated in the past, but that he had misplaced the needed information for such a comparison [...]

Dependent Variable

The attraction measure consisted of 20 items [...]

Subjective Experience Variables

A number of short measures designed to assess the subject’s perceptions of various characteristics of the research experience were included in the post-test battery. [...]