The document provides a template for reporting the results of a two-sample z-test for proportions. It includes an example comparing the proportion of birth defects between residents exposed to contaminated well water (16 defects from 414 births, or 4%) and residents not exposed (3 defects from 228 births). The z-test results show residents exposed to contaminated water had a statistically significantly higher rate of birth defects (z = 2.35, p = .001).

1. Reporting Two-Sample Z-Test For
Proportions

2. Template

3. Template
[insert a description of a sample proportion]

4. Template
[insert a description of a sample proportion] [Insert the
result in terms of a proportion or a percentage]

5. Template
[insert a description of a sample proportion] [Insert the
result in terms of a proportion or a percentage] is
statistically significantly

6. Template
[insert a description of a sample proportion] [Insert the
result in terms of a proportion or a percentage] is
statistically significantly [insert “different”, “higher”,
“lower”, “more”, “less”, etc.] [insert the dependent
variable]

7. Template
[insert a description of a sample proportion] [Insert the
result in terms of a proportion or a percentage] is
statistically significantly [insert “different”, “higher”,
“lower”, “more”, “less”, etc.] [insert the dependent
variable] than

8. Template
[insert a description of a sample proportion] [Insert the
result in terms of a proportion or a percentage] is
statistically significantly [insert “different”, “higher”,
“lower”, “more”, “less”, etc.] [insert the dependent
variable] than [insert a description of the other sample
proportion],

9. Template
[insert a description of a sample proportion] [Insert the
result in terms of a proportion or a percentage] is
statistically significantly [insert “different”, “higher”,
“lower”, “more”, “less”, etc.] [insert the dependent
variable] than [insert a description of the other sample
proportion], z = 0.00, p = .000.

10. Template
[insert a description of a sample proportion] [Insert the
result in terms of a proportion or a percentage] is
statistically significantly [insert “different”, “higher”,
“lower”, “more”, “less”, etc.] [insert the dependent
variable] than [insert a description of the other sample
proportion], z = 0.00, p = .000.

11. Here is an example problem:

12. Here is an example problem:
In a small town in Massachusetts, a town well supplied
water that was contaminated by industrial chemicals to
the west side residents but not to the east side
residents, because they used a different well.

13. Here is an example problem:
In a small town in Massachusetts, a town well supplied
water that was contaminated by industrial chemicals to
the west side residents but not to the east side
residents, because they used a different well. During
that period of time a sample of 414 births on the west
side showed 16 birth defects and a sample of 228
births on the east side showed 3 birth defects.

14. Here is an example problem:
In a small town in Massachusetts, a town well supplied
water that was contaminated by industrial chemicals to
the west side residents but not to the east side
residents, because they used a different well. During
that period of time a sample of 414 births on the west
side showed 16 birth defects and a sample of 228
births on the east side showed 3 birth defects. A law
suit is pending against the city for negligence.

15. Here is an example problem:
In a small town in Massachusetts, a town well supplied
water that was contaminated by industrial chemicals to
the west side residents but not to the east side
residents, because they used a different well. During
that period of time a sample of 414 births on the west
side showed 16 birth defects and a sample of 228
births on the east side showed 3 birth defects. A law
suit is pending against the city for negligence. How
strong is their evidence statistically?

16. Step 1 - [insert a description of a sample proportion]
“Residents who were exposed to water contaminated with
industrial chemicals”

17. Step 1 - [insert a description of a sample proportion]
“Residents who were exposed to water contaminated with
industrial chemicals”
Step 2 – “had statistically significantly” [insert “different”, “higher”, “lower”,
“more”, “less” etc.]
“had statistically significantly more”

18. Step 1 - [insert a description of a sample proportion]
“Residents who were exposed to water contaminated with
industrial chemicals”
Step 2 – “had statistically significantly” [insert “different”, “higher”, “lower”,
“more”, “less” etc.]
“had statistically significantly more”
Step 3 - [insert the dependent variable]
“birth defects”

19. Step 1 - [insert a description of a sample proportion]
“Residents who were exposed to water contaminated with
industrial chemicals”
Step 2 – “had statistically significantly” [insert “different”, “higher”, “lower”,
“more”, “less” etc.]
“had statistically significantly more”
Step 3 - [insert the dependent variable]
“birth defects”
Step 4 – [Insert the result in terms of a proportion or a percentage]
(.04)

20. Step 1 - [insert a description of a sample proportion]
“Residents who were exposed to water contaminated with
industrial chemicals”
Step 2 – “had statistically significantly” [insert “different”, “higher”, “lower”,
“more”, “less” etc.]
“had statistically significantly more”
Step 3 - [insert the dependent variable]
“birth defects”
Step 4 – [Insert the result in terms of a proportion or a percentage]
(.04)
Step 5 – “than” [insert a description of the other sample proportion],
“than residents who were not exposed to the contaminated water”

21. Step 1 - [insert a description of a sample proportion]
“Residents who were exposed to water contaminated with
industrial chemicals”
Step 2 – “had statistically significantly” [insert “different”, “higher”, “lower”,
“more”, “less” etc.]
“had statistically significantly more”
Step 3 - [insert the dependent variable]
“birth defects”
Step 4 – [Insert the result in terms of a proportion or a percentage]
(.04)
Step 5 – “than” [insert a description of the other sample proportion],
“than residents who were not exposed to the contaminated water”
Step 6 – insert z statistic
“z = 2.35”

22. Step 1 - [insert a description of a sample proportion]
“Residents who were exposed to water contaminated with
industrial chemicals”
Step 2 – “had statistically significantly” [insert “different”, “higher”, “lower”,
“more”, “less” etc.]
“had statistically significantly more”
Step 3 - [insert the dependent variable]
“birth defects”
Step 4 – [Insert the result in terms of a proportion or a percentage]
(.04)
Step 5 – “than” [insert a description of the other sample proportion],
“than residents who were not exposed to the contaminated water”
Step 6 – insert z statistic
“z = 2.35”
Step 7 – insert p value
“p = .001

23. Final Two-Sample Z-Test Report:

24. Final Two-Sample Z-Test Report:
Residents who were exposed to water contaminated
with industrial chemicals had statistically significantly
more birth defects (.04) than residents who were not
exposed to the contaminated water. z = 2.35, p = .001.

25. Residents who were exposed to water contaminated
with industrial chemicals had statistically significantly
more birth defects (.04) than residents who were not
exposed to the contaminated water. z = 2.35, p = .001.