Week 5 Flashcards
How can we define statistics?
The common method used to draw reliable conclusions from quantitative data
What is the confidence interval (CI)?
A measure of how confident we are in our results - typically we adopt a confidence level of 95% and calculate a range
What is the difference between descriptive statistics and inferential statistics?
Descriptive is means, modes etc but inferential is correlations and forming a hypothesis
What is nominal data?
Categorical data
What is ordinal data?
Ordered or ranked data with undefined distance between steps. For example, is ice cream tasty/neutral/not tasty?
What is interval data?
Ordered data with equal distance between steps
What is standard deviation?
The mean deviation from the mean - a measure of how dispersed the data is
What is the difference between interval data and ratio data?
Ratio data has a defined 0
How are interval and ratio data often grouped?
Parametric or contiguous
What is hypothesis testing?
Defining a hypothesis and a null hypothesis with the goal of determining if we can reject the null hypothesis
What does a significant result mean, given a significance level of 5%?
The chance of getting the results we get, even is the null hypothesis is true, is below 5%
What is a Type 1 error?
Reject a true null hypothesis (false positive)
What is a Type 2 error?
Accept a false null hypothesis (false negative)
Which type of errors are we more likely to accept?
We accept a higher risk of type 2 errors, in order to have a lower risk of type 1 errors
What is a T-test?
Used to test if the mean is different from a reference value - provides a 95% CI
What is an independent sample T-test?
Provides a 95% CI of THE DIFFERENCE
What is the difference between an independent sample t-test and a paired sample t-test?
A paired sample test is usually used to test differences from pre-post tests, for example after a measure is implemented
What is one way to assess distribution form in normal distribution tests?
Looking at curves in graphs
What is a CHI2 test?
Used to test if the frequency of observations is different from some reference frequency (commonly even distribution)
What does a return value of 1 mean in a correlation test?
Perfect correlation
What does a return value of -1 mean in a correlation test?
No correlation
What does positive results bias mean?
Research is prone to favour positive outcomes
What is p-hacking?
Shotgunning statistical tests until something comes back positive
What is thematic analysis?
A systematic procedure for generating codes and themes from qualitative data
What is the difference between open and closed analysis?
Whether you have decided on the themes in advance or if you identify them during the analysis
