Collect data on a measurement variable for which the difference in the means for two conditions or groups is of interest to you. Collect at least 30 observations for each condition or group. Using the data, compute an approximate 95% confidence interval for the difference in the means of the populations from which you drew your observations. Explain how you collected your samples, and note whether your method would be likely to result in any biases if you tried to extend your sample results to the populations. Interpret the 95% confidence interval to make a conclusion about the difference in the means of the populations or conditions.
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