Microsoft Office Tutorials and References

In Depth Information

Or
Alumni who were female Biology majors were signiﬁcantly less satisﬁed with

their academic experience in the Biology department at State University than

male Biology majors (4.37 vs. 7.26).

Both of these conclusions are accurate, so you can decide which one you want to

write. It is your choice.

Also, note that the mean scores in parentheses at the end of these conclusions

must match the sequence of the two groups in your conclusion. For example, if you

say that: “Male alumni were signiﬁcantly more satisﬁed than female alumni,” the

end of this conclusion should be: (7.26 vs. 4.37) since you mentioned males ﬁrst,

and females second.

Alternately, if you wrote that: “Female alumni were signiﬁcantly less satisﬁed

than male alumni,” the end of this conclusion should be: (4.37 vs. 7.26) since you

mentioned females ﬁrst, and males second.

Putting the two mean scores at the end of your conclusion saves the reader from

having to turn back to the table in your research report to ﬁnd these mean scores to

see how far apart the mean scores were.

Now, let’s discuss FORMULA #1 that deals with the situation in which both

groups have a sample size greater than 30.

Objective
: To use FORMULA #1 for the two-group t-test when

both groups have a sample size greater than 30

5.2 Formula #1: Both Groups Have a Sample Size Greater

Than 30

The ﬁrst formula we will discuss will be used when you have two groups with a

sample size greater than 30 in each group and one measurement on each member in

each group. This formula for the two-group t-test is:

X
1

X
2

S
X
1
X
2

t

¼

(5.2)

where

s

S
1

n
1
þ

S
2

n
2

S
X
1
X
2
¼

(5.3)

and where degrees of freedom

¼

df

¼

n
1
þ

n
2

2

(5.1)

Search JabSto ::

Custom Search