Data 44 elementary school students were randomly assigned to

Data: 44 elementary school students were randomly assigned to one of two methods of teaching reading comprehension. Both methods were designed so that they could be delivered to individual students rather than to whole classes. Students

Solution

(1)(a) Null and alternative hypotheses

Let mu_dbar be the mean difference between Basal and Basal

Null hypothesis: mu_dbar=0

Alternative hypothesis: mu_dbar not equal to 0

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(b) Numeric value of the test statistic here

The test statistic is

t=mean difference/ std. error

=-2.3636/0.5276

=-4.48

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(c) Value of (or useful range for) the p-value

It is a two-tailed test.

The degree of freedom =n-1=22-1=21

So the p-value= 2*P(t with df=21 <-4.48) = 0.0002 (from student t table)

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(d) Conclusion in context of these data (not just