The Statistics Test - The Sign Test Flashcards
Hypothesis
A testable statement which states relationship or difference between variables being examined
Null hypothesis
Hypothesis which states there will be no relationship or difference between variables being examined
Statistical testing
Way of determining whether the null hypothesis should be accepted or rejected, so the hypothesis can be accepted or declined
Three types of data used in statistical testing
Nominal data
Ordinal data
Interval data
Nominal data
Data represented in form of categories
Example of nominal data
Male or female
Ordinal data
Data that is ranked
Example of ordinal data
How much do you like psychology on a scale of 1-10?
Why does ordinal data lack precision?
Because it’s based on subjective opinion rather than objective measures
What type of dat isn’t a part of statistical testing?
Ordinal data
Interval data
Data based on accepted units of measurement
Example of interval data
Time
Temperature
Weight
What is the most precise and sophisticated form of data in psychology?
Interval data
What type of data is most commonly used for the sign test?
Nominal data
What is the sign test used to determine?
Whether the difference found in results is significant
What do we need to be looking for when using the sign test?
We need to be looking for a difference rather than association
What experimental design do we need to have to use the sign test?
Repeated measures design
What type of data do we need to use the sign test?
Nominal data
What signs do we use to indicate a positive or negative difference in the table of results when using a sign test?
+ for positive
- for negative
After indicating the positive and negative differences in data, what do we do when using the sign test?
We add up to amount of positive differences and negative differences
How do you calculate the sign value (S)?
Add up the amount of positive differences and negative differences. Whichever differences occurs the least frequently is the sign value
Anagram for remembering the sign test
SNoRD
S of SNoRD
Sign
N of SNoRD
Nominal
R of SNoRD
Repeated measures
D of SNoRD
Difference
Why will there always be a null hypothesis alongside the working hypothesis?
Because you need to test for a statistical significance
Why do all studies have a significance level?
To check for significant differences or relationships
What is the accepted level of probability in psychology?
0.05 or 5%
If there is a less than 5% or 0.05 probability that the results occurred by chance, what was the difference likely to be due to?
The manipulation of the IV
When the statistical test has been calculated, what value is the researcher left with?
The calculated value
What value does the calculated value need to be compared to?
The critical value
Why does the calculated value have to be compared with the critical value?
To decide whether the result is significant or not
What are the critical values for a sign test given in?
A table of critical values
What do you need to know to use the table of critical values?
Significance level desired
Number of participants (N)
Whether the hypothesis is directional or non-directional
Repeated measures
Participants are measured two or more times on the dependent variable, rather than different participants being measured for each DV
