Introduction To Statistics

Question

Suppose men always married women who were 10 percent shorter than they were. The correlation coefficient of the heights of married couples would be

Answer

1.0 since the height of the man is always predictable from the height of the woman

Question

We measure heights and weights of 100 twenty-year old male college students. Which will have the higher correlation

Answer

Both will have the same correlation

Question

Suppose the correlation coefficient between heights (as measured in feet) versus weight (as measured in pounds) is 0.40. What is the correlation coefficient of height measured in inches versus weight measured in ounces? [12 inches = one foot; 16 ounces = one pound]

Answer

0.4

Question

An investigator is studying the relation between the physical and intellectual growth of primary school children (grades 1-6). At each grade level, she notes that the correlation between the height of children and the size of their vocabulary is zero. For all students in the school, the correlation is likely to be

Answer

Positive

Question

A summary measure that describes any given characteristic of the population is known as a ___________

Answer

Parameter

Question

A _________ sample is formed by selecting one unit at random and then selecting additional units at evenly spaced intervals until the sample has been formed

Answer

Systematic

Question

Laspeyre’s index numbers possess ___________

Answer

Upward bias

Question

Most commonly used index number is____________

Answer

None

Question

Investor wishing to invest N100,000 in one of three possible investment alternatives, A, B, and C is an example of

Answer

Decision making under uncertainty

Question

The mean of a distribution is 23, the median is 24, and the mode is 25.5. It is most likely that this distribution is:

Answer

Negatively Skewed

Question

The mean of a distribution is 14 and the standard deviation is 5. What is the value of the coefficient of variation?

Answer

0.357

Question

The mean deviation of the series (a, a + d, a +2d cdots + 2n) from its mean is

Answer

n (n +1) d /2n +1

Question

A student obtained the mean and the standard deviation of 100 observations as 40 and 5.1. It was later found that one observation was wrongly copied as 50, the correct figure being 40. Find the correct mean and the S.D

Answer

Mean = 39.9, S.D =5

Question

For a negatively skewed distribution, the correct inequality is____________

Answer

Mean

Question

What percentage of values is greater the 3rd quartile?

Answer

0.25

Question

Which of the following is a unit less measure of dispersion?

Answer

Coefficient of variation

Question

Individual data is another wise called as ___________

Answer

raw data

Question

The data given as 5, 7, 12, 17, 79, 84, and 91 will be called as____________

Answer

An individual series

Question

Which of the following example does not constitute an infinite population?

Answer

  Population of heights of 15 year old children.

Question

In a web-based survey, customers are asked to rate your company’s product on the following scale: Excellent, good, average, poor. The above scale is _____________________

Answer

ordinal

Question

Suppose men always married women who were 10 percent shorter than they were. The correlation coefficient of the heights of married couples would be

Answer

1.0 since the height of the man is always predictable from the height of the woman

Question

We measure heights and weights of 100 twenty-year old male college students. Which will have the higher correlation

Answer

Both will have the same correlation

Question

Suppose the correlation coefficient between heights (as measured in feet) versus weight (as measured in pounds) is 0.40. What is the correlation coefficient of height measured in inches versus weight measured in ounces? [12 inches = one foot; 16 ounces = one pound]

Answer

0.4

Question

An investigator is studying the relation between the physical and intellectual growth of primary school children (grades 1-6). At each grade level, she notes that the correlation between the height of children and the size of their vocabulary is zero. For all students in the school, the correlation is likely to be

Answer

Positive

Question

A summary measure that describes any given characteristic of the population is known as a ___________

Answer

Parameter

Question

A _________ sample is formed by selecting one unit at random and then selecting additional units at evenly spaced intervals until the sample has been formed

Answer

Systematic

Question

Laspeyre’s index numbers possess ___________

Answer

Upward bias

Question

Most commonly used index number is____________

Answer

None

Question

Investor wishing to invest N100,000 in one of three possible investment alternatives, A, B, and C is an example of

Answer

Decision making under uncertainty

Question

The mean of a distribution is 23, the median is 24, and the mode is 25.5. It is most likely that this distribution is:

Answer

Negatively Skewed

Question

The mean of a distribution is 14 and the standard deviation is 5. What is the value of the coefficient of variation?

Answer

0.357

Question

The mean deviation of the series (a, a + d, a +2d cdots + 2n) from its mean is

Answer

n (n +1) d /2n +1

Question

A student obtained the mean and the standard deviation of 100 observations as 40 and 5.1. It was later found that one observation was wrongly copied as 50, the correct figure being 40. Find the correct mean and the S.D

Answer

Mean = 39.9, S.D =5

Question

For a negatively skewed distribution, the correct inequality is____________

Answer

Mean

Question

What percentage of values is greater the 3rd quartile?

Answer

0.25

Question

Which of the following is a unit less measure of dispersion?

Answer

Coefficient of variation

Question

Individual data is another wise called as ___________

Answer

raw data

Question

The data given as 5, 7, 12, 17, 79, 84, and 91 will be called as____________

Answer

An individual series

Question

Which of the following example does not constitute an infinite population?

Answer

  Population of heights of 15 year old children.

Question

In a web-based survey, customers are asked to rate your company’s product on the following scale: Excellent, good, average, poor. The above scale is _____________________

Answer

ordinal