watching tv: in 2012, the general social survey asked a sample of 1310 people how much time they spend\t watching tv each day. The mean number of hours was 2.8 with a standard deviation of 2.6. A sociologist claims that people watch a mean of 3 hours of TV per day. Do the data provide sufficient evidence to conclude that the mean hours of TV watched per day is less the claim? Use the a=0.5 level of significance and the P-value method with the TI-84 Plus calculator.

(a) State the appropriate null and alternate hypotheses.

H0: Mu = 3
H1: Mu < 3

This hypothesis test is a _____ test.

(b) Compute the P-value. Round the answer to at least four decimal places

P-value =

Respuesta :

Answer:

a) Null hypothesis:[tex]\mu \geq 3[/tex]  

Alternative hypothesis:[tex]\mu < 3[/tex]  

This hypothesis test is a left tailed test.

b) [tex]t=\frac{2.8-3}{\frac{2.6}{\sqrt{1310}}}=-2.784[/tex]  

The p value for this case can be calculated with this probability:  

[tex]p_v =P(z<-2.784)=0.0027[/tex]  

We can conduct the test with the Ti84 using the following steps:

STAT>TESTS>T-test>Stats

We input the value [tex]\mu_o =3, \bar X= 2.8, s_x = 2.6, n=1310[/tex] and for the alternative we select [tex]< \mu_o[/tex]. Then press Calculate.

And we got the same results.  

Step-by-step explanation:

Information given

[tex]\bar X=2.8[/tex] represent the sample mean

[tex]s=2.6[/tex] represent the population standard deviation  

[tex]n=1310[/tex] sample size  

[tex]\mu_o =3[/tex] represent the value to test

[tex]\alpha=0.5[/tex] represent the significance level for the hypothesis test.  

t would represent the statistic

[tex]p_v[/tex] represent the p value for the test

Part a) System of hypothesis

We want to test if the true mean is less than 3, the system of hypothesis would be:  

Null hypothesis:[tex]\mu \geq 3[/tex]  

Alternative hypothesis:[tex]\mu < 3[/tex]  

This hypothesis test is a left tailed test.

Part b

The statistic is given by:

[tex]t=\frac{\bar X-\mu_o}{\frac{s}{\sqrt{n}}}[/tex] (1)  

Replacing the info given we got:

[tex]t=\frac{2.8-3}{\frac{2.6}{\sqrt{1310}}}=-2.784[/tex]  

The p value for this case can be calculated with this probability:  

[tex]p_v =P(z<-2.784)=0.0027[/tex]  

We can conduct the test with the Ti84 using the following steps:

STAT>TESTS>T-test>Stats

We input the value [tex]\mu_o =3, \bar X= 2.8, s_x = 2.6, n=1310[/tex] and for the alternative we select [tex]< \mu_o[/tex]. Then press Calculate.

And we got the same results.