7.45 Wheat prices revisited.
Example 7.12 (pages 384–385) gives summary statistics for the price of wheat in January and July. The two sample standard deviations are relatively close, so we may be willing to assume equal population standard deviations. Calculate the pooled test statistic and its degrees of freedom from the summary statistics. Use Table D to assess significance. How do your results compare with the unpooled analysis in the example?
7.45
. The data give evidence that there is a difference between the January and July wheat prices. The results are nearly identical to the unpooled analysis.