Harper MTH165 Homework Section 7.3 Latest 2020 MAY

MTH165 ELEMENTARY STATISTICS

Homework Section 7.3

In this section you learned how to perform a hypothesis test for a single mean use T-Test

In this section you had (qualitative/quantitative) data.  In this case we use the parameter ___ and the random variable _

What input screen will you use in this section to compute the sample statistic, test statistic and p-value? 

What is the formula for the test statistic in this section?  t =____________________

Fill in the following as you work through your given problems in MyOpenMath

1.            individual object: _______________ ________________________________

List given numbers with correct symbols: ______________________________________________

P: The mean carbon dioxide emissions of all countries

H:

μ = 4.87 metric tons per capita

μ < 4.87 metric tons per capita

A: Use StatCrunch to make a modified boxplot and normal probability plot (QQ plot) and submit graphs.

Since quantitative information was collected from each object, what conditions do we need to check? Check all that apply.

n≥30 or normal population

σ is unknown

no outliers in the data

N:

The conditions are met to use a T- test

T:

The symbol and value of the random variable on this problem are as follows

X ?=3.3308

t = -3.77

O:

P value = 0.0002

M:

Since the p-value <= 0.03, we reject H0 

S:

There is significant evidence to conclude the mean carbon dioxide emissions of all countries is less than 4.87 metric tons per capita

2.            individual object: __________

                List given numbers with correct symbols: _____ _________________________________________

P:

The mean forward sway of all elderly people

H:

μ = 18.125 mm

μ > 18.125 mm

A: Use StatCrunch to make a modified boxplot and normal probability plot (QQ plot) and submit graphs.

Since quantitative information was collected from each object, what conditions do we need to check?

n≥30 or normal population

σ is unknown

no outliers in the data

No, the modified boxplot shows no outliers.

N:

n= 46 which is >=  30

Not necessary to check since the sample size is at least 30.

T-Test

T:

The symbol and value of the random variable on this problem are as follows:

X ?=25.13

t = 4.70

O:

P value = 0.0000

M:

Since the p-value <= 0.09 we reject H0

S:

There is significant evidence to conclude the mean forward sway of all elderly people is more than 18.125 mm

                What type of error may have been made in the conclusion on problem 1?  ___________________

                What type of error may have been made in the conclusion on problem 2?  ____________________

                When doing inferential statistics you need to keep in mind that although you are making educated guesses about the population, they are still _______________.

                What are the two reasons why a sample result may be different from the claim about the population?

1.            The claimed population parameter is incorrect

2. We are just seeing a chance random sample fluctuation (sampling error)