Question

In: Statistics and Probability

Suppose that a mean of 68.5% of dogs can identify their owners by sound alone (13%...

Suppose that a mean of 68.5% of dogs can identify their owners by sound alone (13% standard deviation). Whereas a mean of 86.4% of cats can identify their owners by sound alone (8% standard deviation). The scores were approximately normally distributed in each group. Use a two-sample t-test to determine if the difference between the two means (N1=20, N2=30) are statistically significant. N1=dogs/N2=cats.

Expert Solution

We are given

Let

Test statistic: will have a t distribution with df.

where

. The critical value of t at 38 df=2.024.

Since the , we reject the null hypothesis.

Hence we conclude that theer is a difference between two means.

orchestra answered 2 years ago

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