# PSY 245 Week 4 Descriptive Statistics Quiz

PSY 245 Week 4 Descriptive Statistics Quiz

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Descriptive Statistics Quiz

Answer each of the following questions (multiple-choice or short-answer) according to the question prompt.

The number that occurs most frequently in a data set is

mean

median

mode

harmonic

What type of graphic presents data in terms of frequencies per category?

Pie chart

Line graph

Bimodal distribution

Histogram

When you are dealing with a normal distribution of scores, which measure of central tendency is preferred?

Mean

Median

Mode

All of the above, as they will be the same in this distribution

The _______ is a single number that represents the total amount of variability in a distribution.

standard deviation

variance

range

mean

Correlation coefficients represent

The degree of relationship between two variables

causality between two relationships

whether the independent variable had an effect

all of the above

Which of the following would probably be negatively correlated?

The number of days in class and exam grade

The height and weight of college students

The number of difficult classes taken and semester GPA

Overall college GPA and graduate school GPA

A perfect positive correlation occurs when

an increase of 1 unit is always accompanied by a proportional increase in the other variable

there is no relationship between the two variables

an increase of 1 unit is always accompanied by a lesser increase in the other variable

an increase of 1 unit is always accompanied by a greater increase in the other variable

You are reading an article that says age and number of sick days taken per year has a correlation of -0.72.  How would you interpret this correlation?

A weak, positive correlation

A weak, negative correlation

A strong, negative correlation

A strong, positive correlation

If a data set has the following data points―5,6,7,6,7―you would expect the standard deviation to be

a small number, because the numbers do not vary much from the mean of 6.2

a large number, because the numbers do not vary much from the mean of 6.2

a large number, because the numbers vary a great deal from the mean of 6.2

a small number, because the numbers vary a great deal from the mean of 6.2

Descriptive statistics are

procedures using the experimental method

procedures used to analyze data after an experiment

procedures used to summarize a set of data

all of the above

The standard deviation is the square root of the

variance

mean

range

sum of the raw scores

Define nominal data, and provide an example.

Define ordinal data, and provide an example.

Define interval data, and provide an example.

Define ratio data, and provide an example.

If you are dealing with percentages that total 100%, the best graph to represent your data is a

bar graph

pie chart

histogram

frequency polygon

If you want to know which score in a data set occurred the most often, you would use a

mean

median

range

mode

Which measure of central tendency is less accurate if there are a few extremely large or extremely small numbers in the data set?

Median

Mode

Mean

Range

Graphical representations of data sets

allow an easy way to represent large sets of numbers

are less confusing than several numbers in a descriptive paragraph

allow a point to be easily understood

all of the above

Which type of graph is frequency used to depict experimental results?

Pie chart

Histogram

Frequency polygon

Line graph