Data analysis: Descriptive stats Flashcards
What is a measure of central tendency?
A general term for any measure of the average value of a set.
What is the median?
The central value in a set of data when values when arranged lowest to highest.
What are the three measures of central tendency?
- Mean,
- Median,
- Mode.
How do you find the median?
Order the numbers from lowest to highest, then find the middle value.
What is the mode?
The most frequently occurring value in a set of data.
Which measure of central tendency considers all values in a data set?
The mean.
What are descriptive statistics?
The use of graphs, tables and summary statistics to identify trends and analyse sets of data.
How do you find the mode?
Identify the number that is most common in the data set.
Why is the mean seen as the most representative measure of central tendency?
Because it considers the weight of all values in the data set.
What is the mean?
The arithmetic average calculated by adding up all the values of a set and dividing by the number of values.
How do you calculate the mean value?
Add up all of the values in a data set, then count the number of values and divide the sum by the number of values.
T / F:
- It is possible to have two values as the mean.
False.
How do you calculate the mode?
Find the most frequently occurring value in a data set.
What does it mean if a set is bi-modal?
There are two modes in the data set.
There can be more than one average for which measure of tendency?
There can be more than 1 mode.
If every score in the data set is different, what is the mode?
There is no mode.
T / F:
- It is possible to have two values as the median.
False.
Which measure of central tendency is used to measure the most ‘typical’ value?
The mode.
Which measure of central tendency can easily be distorted by an anomalous value?
The mean.
T / F:
- It is possible to have two values as the mode.
True.
What are measures of dispersion?
The general term for any measure of spread or variation in a set of scores.
What is the range?
The total dispersion in a set of scores.
What does a smaller standard deviation mean?
That there is little dispersion or spread within a set of data.
How would a tightly clustered data set be represented in a standard deviation?
The standard deviation would be low.
How is the range calculated?
The lowest value is subtracted from the highest value.
Which measure of dispersion is the most precise?
Standard deviation, because it includes all values within the final calculation.
How do anomalous values affect the standard deviation?
They heavily distort them.
What does a large standard deviation mean?
That there is greater dispersion or spread within a set of data.
What are the main two measures of dispersion?
Range and Standard Deviation.
What is the standard deviation?
A measure of the dispersion within a set of scores, telling us how much scores differentiate from the mean.
