Mathematical Skills Flashcards
(29 cards)
What is the mean?
The mean is a measure of central tendency. It shows the average or expected value in a set of data
What is a strength of the mean?
Easy to calculate mathematically, gives a precise value, and useful for statistical tests
What is a strength of the mean?
Easy to calculate mathematically, gives a precise value, and useful for statistical tests
What is a weakness of the mean?
Can be affected by outliers, can give a value not originally in the data set
What is median?
The middle value in a set of data that is organised by increasing value
What is the strength of the median?
Not affected by outliers, will always give a value originally in the data set
What is the weakness of the median?
Not a useful as other statistical test, required sorted and ordered data
What is the mode?
Provides the most frequent or common value in a data set
What is the strengths of the mode?
A useful way of calculating the average when the data is nominal
What is the weaknesses of the mode?
There may be multiple modes, there may not be a mode at all, the mode may not represent the spread of the data in an accurate way
What is the range?
A measure of dispersion - the difference between the highest and lowest value in a set of data
What are the strengths of the range?
Easy to calculate and gives a good idea of the spread of data
What are the weaknesses of the range?
Is affected by outliers and is not useful for other statistical calculations
How do you calculate the variance?
Calculate the mean, subtract the mean from every value in the table (the new value is called d), square each value of d, add up each value of d squared, divide this number by the amount of numbers of values in the table
How do you calculate the standard deviation?
Follow the exact same steps as the variance, at the end square rot your answer to get the standard deviation.
What are parametric tests?
They assume that the poulation that the data is drawn form is normally distributed
What are non-parametric tests?
They are used when this assumption cannot be made. These tests are often used due to difficulty in gaining normally distributed populations.
What is nominal data?
It is used to label or describe variables but have no quantitative values
What is ordinal data?
It is used to quantify variables, but the difference between each value is not known or quantifiable
What is interval data?
It is quantitative data in which the difference or scale between the values is precise and measurable. They normally have scientific units
What are the characteristics of a positive skew?
Peak closer to the axis, the slide going to the right
What are the characteristics of a negative skew?
Peak further from the axis, the slide going towards the axis
What is the test that goes with independent measures and nominal data?
Chi Squared
What is the test that goes with repeated measures and nominal data?
Binomial Sign Test
