Preliminary data analyses indicate that the assumptions for
using pooled t-procedures are satisfied. Independent random
samples of
104 plots with cropland and98 plots with grassland yielded the given summary statistics for the number of species of bird. At the55% significance level, do the data provide sufficient evidence to conclude that a difference exists in the mean number of species in the two regions? |
|
Let
mu 1μ1
be the mean number of species of bird in the cropland
mu 2μ2
the mean number of species in the grassland. What are the correct hypotheses to test?
A.
Upper H 0H0:
mu 1μ1equals=mu 2μ2
Upper H Subscript aHa:
mu 1μ1greater than>mu 2μ2
B.
Upper H 0H0:
mu 1μ1equals=mu 2μ2
Upper H Subscript aHa:
mu 1μ1not equals≠mu 2μ2
C.
Upper H 0H0:
mu 1μ1less than<mu 2μ2
Upper H Subscript aHa:
mu 1μ1equals=mu 2μ2
D.
Upper H 0H0:
mu 1μ1not equals≠mu 2μ2
Upper H Subscript aHa:
mu 1μ1equals=mu 2μ2
E.
Upper H 0H0:
mu 1μ1greater than>mu 2μ2
Upper H Subscript aHa:
mu 1μ1equals=mu 2μ2
F.
Upper H 0H0:
mu 1μ1equals=mu 2μ2
Upper H Subscript aHa:
mu 1μ1less than<mu 2μ2
Compute the test statistic.
tequals=nothing
(Round to three decimal places as needed.)
Determine the critical value or values.
nothing
(Round to three decimal places as needed. Use a comma to separate answers as needed.)
What is the conclusion of the hypothesis test?
Since the test statistic
is
is
is not
in the rejection region,
do not reject
do not reject
reject
Upper H 0H0.
Conclude that the data
provide
provide
do not provide
sufficient evidence that a difference exists in the mean number of species in the two regions.
Preliminary data analyses indicate that the assumptions for using pooled t-procedures are satisfied. Independent random samples...
Preliminary data analyses indicate that the assumptions for using pooled t-procedures are satisfied. Independent random samples of 103 plots with cropland and 99 plots with grassland yielded the given summary statistics for the number of species of bird. At the 5% significance level, do the data provide sufficient evidence to conclude that a difference exists in the mean number of species in the two regions? Cropland Grassland x overbar 1 equals 14.12 x overbar 2 equals 15.87 s 1 equals...
Preliminary data analyses indicate that the assumptions for using pooled t-procedures are satisfied. Independent random samples of 102 plots with cropland and 100 plots with grassland yielded the given summary statistics for the number of species of bird. At the 1% significance level, do the data provide sufficient evidence to conclude that a difference exists in the mean number of species in the two regions? Cropland Grassland x overbar 1 = 14.51 x overbar 2 = 15.33 s 1 =...
Preliminary data analyses indicate that you can reasonably consider the assumptions for using pooledt-procedures satisfied. Independent random samples of 102 plots with cropland and100 plots with grassland yielded the given summary statistics for the number of native species. Cropland Grassland x overbar 1 =14.88 x overbar 2= 15.87 s 1 =4.51 s 2 = 4.75 n 1=102 n 2= 100 Determine a 95% confidence interval for the difference between the mean number of native species in the two regions. HI,...
Preliminary data analyses indicate that you can reasonably consider the assumptions for using pooled t-procedures satisfied. Independent random samples of 103 plots with cropland and 99 plots with grassland yielded the given summary statistics for the number of native species. Cropland: x bar 1= 14.62 s1=4.74 n1=103 Grassland: x bar 2= 15.89 s2=4.91 n2=99 The 98% confidence interval is from ? to ?
fill in the blank is 1. is not/is 2. do not reject/reject and 3. provide/do not provide Question Help Preliminary data analyses indicate that the assumptions for using pooled t-procedures are satisfied. Independent random samples of 102 plots with cropland and 100 plots with grassland Cropland Grassland x1 14.33x215.86 1 4.62 82-4.74 n1 -102 n2 100 ded the given summary statistics for the number of species of bird. At the 1% significance level do the data provide sufficient evidence to...
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