Research methods data Flashcards
what is a correlation
mathematical technique to see the relationship between two co variables to see the strength and direction with no manipulation of an ice so cannot establish cause and effect relationship
what are the different types of correlation
positive correlation as one variable increases the other variable also increases
how is experimental different to correlation
experimental is changing the independent variable and seeing the effecton the dependent variable wheras in correlation there is no manipulation so a cause and effect relationship cannot be conducted or observed
strength of correlation
it is quick and easy and economical to see the relationships between two co variables so a quick way to analyse data and information quickly
toolf for research by assessing the strength of a relationship and allows further investigations and experiments in order to establish a cause and effect relationship based on the variable
You can also investigate the relationship in unethical situations
what is the weakness of correlation
lack of manipulation of iv means that a cause and effect cannot be establishe so know there Is a relationship but don’t know what it is cause by
also there may be a third variable that link the two variables together which haven’t been accounted for so the correlation may be misinterprated
what is central tendency
Performance of a group using a number or a trend
what is the mean and advantages and disadvantages
Interpretation
the mean accounts for all the numbers in a sample so the most repesentetive add all the numbers and divide by the numbers present a strength is that it count for all numbers so take all values when creating a mean so most sensitive
includes outliers which can make the mean appear too large or too small which may not actually be representative of the sample
Higher mean would mean higher accuracy and scoring and lower in reaction time
what is the median advantages and disadvantages
the median is the middle value when ordered the information one strength is that it measures the middle number in the data and isn’t affected by outliers
however not sensitive as not data or values are included
what is the mode
the most occurring value in a data set it ignores outiers as not so sensitive
howver it doesn’t take into account all the values especially if there are different patterns and can stray from the mean and median significantly
Higher mode compared to another means better performance
what is dispersion
to see how the data and cores are spread out in a data set
what is the range
highest value minus the lowest value it is a strength as it accounts for all values in the data set and shows the overall range and easy to calculate
it can be distorted by an outlier so may be unrepesentitive
what is standard deviation
how much the values deviate from the mean the larger the spread of data the likelihood that the dv had been affected by other variables aside from the iv more consistency on the results
strength is that it take into account all the values and how it strays from the mean so repesentitive howveer it takes long and it can be affected by extreme values
what is normal distribution
most people are based in the middle of the graph median mean and mode the line never touches zero as values are always possible it occurs when a test is a right difficulty
what is a positive skew
most of the distribution is on the far left of the graph with the mode median and mean with a long tail on the right the pulls the tail to the right with those who have scored really highly so pull the mean to the right most people score low this may because the test is too difficult
what is a negative skew
most of the distribution is on the right of the graph the mode is far left then median then mean the test is too esy and the mean is distorted to the left by those who score poorly it is an easy exam so many score highly