V. Hypothesis test and confidence intervals.
1. A sample (n) is taken at random from a population and
produces (the sample)
A
= 1100, S = 200. Try the following hypothesis: If we assume the
following size of
sample n = 36
a, Is there evidence that the average μx is less than 1200? α =
.10
H0: μx = 1200
H1: μx <1200
* For the previous test (item a) estimate the p-value
* Determine the power of the previous hypothesis test. (1-β)
* Estimate 95% confidence interval for the true average
value.
SAW. Linear Regression and Correlation.
The following n = 5 data were collected for a linear regression study for two variables.
26 24 144 158 136
ΣX ΣY ΣXY ΣX ^ 2 ΣY ^ 2
_____ X Y
2 2
Four. Five
5 3
7 7
8 7
to. Develop a graph X, Y (Scatter diagram)
* Compute the linear regression equation
* If x = 10, what value would you estimate for "y" the linear
regression equation?
* Test the following hypothesis for the previously calculated
linear regression slope:
Use an alpha of α = .10
MSE = 1.544
Ho: β = 0 There is no linear relationship between X and Y
Ha: β> 0 There is some positive linear relationship between X
and Y
* Compute the correlation coefficient r
* Test the following hypothesis for the previously calculated
correlation coefficient:
Use an alpha of α =
.01
Ho: ρ = 0 There is no relationship between X and Y
Ha: ρ> 0 There is some positive relationship between X and Y
* Compute the correlation coefficient r
* Test the following hypothesis for the previously calculated
correlation coefficient:
Use an alpha of α =
.01
Ho: ρ = 0 There is no relationship between X and Y
Ha: ρ> 0 There is some positive relationship between X and Y
VI1. Goodness of fit test for the Poisson distribution
We want to test the following hypothesis for a given study.
Ho The cars parked in the houses follow a Poisson distribution
with λ = 1.3.
Ha Cars parked in houses Do not follow a Poisson distribution with
λ = 1.3.
Use an α = .10 750 observations were taken. The data of a study are the following:
Number of cars Frequency λ=1.3
P(x)
0
170
.2725
1
270
.3543
2
200
.2303
3 o mas
110
.1429
V. Hypothesis test and confidence intervals.
The hypotheses are
Given the sample size and sample mean , sample standard deviation . Degrees of freedom is .
The test statistic is
The P-value is
The power of the test is
The two sided confidence interval for population mean based on the sample data is
The 95% confidence interval for the true average value is
V. Hypothesis test and confidence intervals. 1. A sample (n) is taken at random from a...
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