Assignment 3 Part 1

	Interval Type	Confidence Level	n	a	z or t?	z or t Value
A	Two Tailed	90	45	.1	z	1.28
B	Two Tailed	95	12	.05	t	2.179
C	One Tailed	95	36	.05	z	1.64
D	Two Tailed	99	180	.01	z	2.32
E	One Tailed	80	60	.2	z	.84
F	One Tailed	99	23	.01	t	2.807
G	Two Tailed	99	15	.01	t	2.947

1.       A Department of the interior in Washington D.C. estimates that the number of particular invasive species in a certain county (Bucks County) should number as follows (averages based on data from the whole state of Pennsylvania) per acre: Asian-Long Horned Beetle, 4; Emerald Ash Borer Beetle, 10; and Golden Nematode, 75.  A survey of 50 fields had the following results:

μ               σ

                Asian-Long Horned Beetle           3.2          0.73

                Emerald Ash Borer Beetle            11.7        1.3

                Golden Nematode                          77           5.71

               

a.       Test the hypothesis for each of these products.  Assume that each are 2 tailed with a Confidence Level of 95% *Use the appropriate test

a.       Asian Long Horned Beetle- Reject the Null Hypothesis

b.      Emerald Ash Borer Beetle- Reject the Null Hypothesis

c.       Golden Nematode- Reject the Null Hypothesis

b.      Be sure to present the null and alternative hypotheses for each as well as conclusions

a.       Null: There is no difference between the number of a particular invasive species in the state of Pennsylvania to the number of the same species in Bucks County.

b.      Alternative: There is a difference between the number of a particular invasive species in the state of Pennsylvania to the number of the same species in Bucks County.

c.       What can ascertained pertaining to the findings about these invasive species in Buck County?

a.       Something is going on in Buck County.  Both the Emerald Ash Borer and Golden Nematode have higher numbers than the state average. One could imply that the county government is not doing enough to help the spread and growth of these invasive species, however, you could also imply without even leaving the computer that the habitat could be very different in Bucks County versus the whole state which would allow for more growth of those species in Bucks County. The same could be said for the Asian Long Horned Beetle except on the other end of the spectrum. Bucks County has a lower average than the state so you could imply that they have little habitat in the county or that the county is doing an exceptional job of eliminating that species.

2.       An exhaustive survey of all users of a wilderness park taken in 1960 revealed that the average number of persons per party was 2.1.  In a random sample of 25 parties in 1985, the average was 3.4 persons with a standard deviation of 1.32 (one tailed test, 95% Con. Level)

a.       Test the hypothesis that the number of people per party has changed in the intervening years.  (State null and alternative hypotheses)

a.       Null: There is no difference between the number of parties in 1960 versus 1985.

b.      Alternative: There is a difference between the number of parties in 1960 versus 1985.

b.      What is the corresponding probability value

a.       I got a T Value of 4.92 after running the numbers and for a one tailed test at 95% confidence level the probability value is 1.711.