Task 1:

# Project Week 6

For these project assignments throughout the course you will need to reference the data in the ROI Excel spreadheet. Download it here.

Using the ROI data set:

1.For each of the 2 majors test the hypothesis at the 5% significance level:

oThe mean ‘Cost’ for a college is $160,000. Be sure to interpret your results.

1.For Business versus Engineering majors conduct a two sample test of the hypothesis at the 10% significance level (assume the variances are not equal):

oThe average ’30-Year ROI’ for Business majors is less than for Engineering Majors. Be sure to interpret your results.

Task 2:

# Relationship of Height and Weight

Using the given Height and Weight data set, follow the steps in the weekly video or on pages 584-585 of the textbook for performing a regression analysis using Excel to analyze the Height and Weight Data set (assume height is the input variable x and weight is the output variable y).

Once you have performed the analysis in Excel, state the correct simple linear regression equation and use the regression equation to predict the weight (in pounds) of a person who is 65 inches tall and the weight (in pounds) of a person who is 100 inches tall.

Why might the regression equation you have found not be a good predication of the weight of someone who is 100 inches tall?

Task 3:

Choose the correct multiple answer

### QUESTION 1

A portion of the population selected to represent the population is called

statistical inference |
||

Data and Statistics |
||

a census |
||

a sample |

5 points

### QUESTION 2

The process of analyzing sample data in order to draw conclusions about the characteristics of a population is called

Data and Statistics |
||

statistical inference |
||

data analysis |
||

data summarization |

5 points

### QUESTION 3

A numerical value used as a summary measure for a sample, such as sample mean, is known as a

population parameter |
||

sample parameter |
||

sample statistic |
||

population mean |

5 points

### QUESTION 4

The set of all possible sample points (experimental outcomes) is called

a sample |
||

an event |
||

the sample space |
||

a population |

5 points

### QUESTION 5

A numerical description of the outcome of an experiment is called a

descriptive statistic |
||

probability function |
||

variance |
||

random variable |

5 points

### QUESTION 6

A description of the distribution of the values of a random variable and their associated probabilities is called a

probability distribution |
||

random variance |
||

random variable |
||

expected value |

5 points

### QUESTION 7

Which of the following is not a characteristic of the normal probability distribution?

The mean, median, and the mode are equal |
||

The mean of the distribution can be negative, zero, or positive |
||

The distribution is symmetrical |
||

The standard deviation must be 1 |

5 points

### QUESTION 8

A theorem that allows us to use the normal probability distribution to approximate the sampling distribution of sample means and sample proportions whenever the sample size is large is known as the

approximation theorem |
||

normal probability theorem |
||

central limit theorem |
||

central normality theorem |

5 points

### QUESTION 9

The value added and subtracted from a point estimate in order to develop an interval estimate of the population parameter is known as the

confidence level |
||

margin of error |
||

parameter estimate |
||

interval estimate |

5 points

### QUESTION 10

Whenever the population standard deviation is unknown and the population has a normal or near-normal distribution, which distribution is used in developing an interval estimation?

standard distribution |
||

z distribution |
||

alpha distribution |
||

t distribution |

5 points

### QUESTION 11

The level of significance

can be any positive value |
||

can be any value |
||

is (1 – confidence level) |
||

can be any value between -1.96 to 1.96 |

10 points

### QUESTION 12

When the p-value is used for hypothesis testing, the null hypothesis is rejected if

p-value ≤ α |
||

α < p-value |
||

p-value ≥ α |
||

p-value = 1 – α |

10 points

### QUESTION 13

The p-value is a probability that measures the support (or lack of support) for the

null hypothesis |
||

alternative hypothesis |
||

either the null or the alternative hypothesis |
||

sample statistic |

10 points

### QUESTION 14

The coefficient of correlation

is the square of the coefficient of determination |
||

is the square root of the coefficient of determination |
||

is the same as r-square |
||

can never be negative |

10 points

### QUESTION 15

Regression analysis is a statistical procedure for developing a mathematical equation that describes how

one independent and one or more dependent variables are related |
||

several independent and several dependent variables are related |
||

one dependent and one or more independent variables are related |
||

None of these alternatives is correct. |

Task 4:

CHoose the correct multiple choice answers :

**QUESTION 1**

A numerical value used as a summary measure for a sample, such as sample mean, is known as a

population parameter |
||

sample parameter |
||

sample statistic |
||

population mean |

5 points

**QUESTION 2**

The 50th percentile is the

mode |
||

median |
||

mean |
||

third quartile |

5 points

**QUESTION 3**

The difference between the largest and the smallest data values is the

variance |
||

interquartile range |
||

range |
||

coefficient of variation |

5 points

**QUESTION 4**

When data are positively skewed, the mean will usually be

greater than the median |
||

smaller than the median |
||

equal to the median |
||

positive |

5 points

**QUESTION 5**

The numerical value of the standard deviation can never be

larger than the variance |
||

zero |
||

negative |
||

smaller than the variance |

5 points

**QUESTION 6**

Which of the following symbols represents the standard deviation of the population?

σ2 |
||

σ |
||

μ |
||

x ̅ |

5 points

**QUESTION 7**

Which of the following symbols represents the mean of the population?

σ2 |
||

σ |
||

μ |
||

x ̅ |

5 points

**QUESTION 8**

Which of the following symbols represents the mean of the sample?

σ2 |
||

σ |
||

μ |
||

x ̅ |

5 points

**QUESTION 9**

Two events are mutually exclusive

if their intersection is 1 |
||

if they have no sample points in common |
||

if their intersection is 0.5 |
||

None of these alternatives is correct. |

5 points

**QUESTION 10**

The range of probability is

any value larger than zero |
||

any value between minus infinity to plus infinity |
||

zero to one |
||

any value between -1 to 1 |

5 points

**QUESTION 11**

The sum of the probabilities of two complementary events is

0 |
||

0.5 |
||

0.75 |
||

1 |

10 points

**QUESTION 12**

The union of events A and B is the event containing

all the sample points belonging to B or A |
||

all the sample points belonging to A or B |
||

all the sample points belonging to A or B or both |
||

all the sample points belonging to A or B, but not both |

10 points

**QUESTION 13**

Events A and B are mutually exclusive. Which of the following statements is also true?

A and B are also independent. |
||

P(A ∪ B) = P(A)P(B) |
||

P(A ∪ B) = P(A) + P(B) |
||

P(A ∩ B) = P(A) + P(B) |

10 points

**QUESTION 14**

The set of all possible sample points (experimental outcomes) is called

a sample |
||

an event |
||

the sample space |
||

a population |

10 points

**QUESTION 15**

If A and B are independent events, then

P(A) must be equal to P(B) |
||

P(A) must be greater than P(B) |
||

P(A) must be less than P(B) |
||

P(A) must be equal to P(A│B) |