BSLEC 3 Flashcards
Techniques that allow us to make inferences about a population based on data that we gather from a sample
INFERENTIAL STATISTICS
Study results will vary from sample to sample strictly due to ___
random chance
allow us to determine how likely it is to obtain a set of results from a single sample
Inferential statistics
This is also known as testing for “statistical significance
Inferential statistics
When you use inferential statistics, you start with a ___and look to see whether the data are consistent with that ___
hypothesis
the product of hypothesis testing via various statistical tests and is claimed to be significant most commonly when the value is 0.05 or less
p value
The value 0.05 is___
arbitrary
(99%) depending on requirements
power
also known as a “false positive”
Type I error
the error of rejecting a null hypothesis when it is actually true.
Type I error
also known as a “false negative”
Type Il error
the error of not rejecting a null hypothesis when the alternative hypothesis is the true state of nature
Type Il error
this is the error of failing to accept an alternative hypothesis when you don’t have adequate power.
Type Il error
there is no significant difference
Null hypothesis
There is a significant difference
Alternative hypothesis
a measure of the researchers’ uncertainty in the sample statistic as an estimate of the population parameter, if less than the whole population is studied.
Confidence interval
usually set at 95% by convention
Confidence interval
_____helps us decide whether two quantities are significantly different but does not tell us how different (degree) they are.
P-VALUES
whilst standard errors shrink with increasing sample size, the researcher should be seeking to reach an optimal sample size, rather than the maximal sample size.
The standard error
. standard deviation, of the effect being studied e the less variability in the sample, the more precise the estimate in the population and therefore a narrower range.
The mean and the variability
the more confident someone wants to be in the obtained results, the higher the confidence interval needs to be, In other words, if a 99% confidence interval is desired then the range will have to be wider, to cover the extra data that needs to be covered over and above the arbitrary 95%,
The degree of confidence required
Probability of an event the relative frequency of this set of outcomes over an Indefinitely large (or Infinite) number of trials
Probability
Any set of outcomes of interest
Event
The set of all possible outcomes of a random phenomenon
Sample space
Events that do not affect each other.
Multiply
Independent Events
Events that affect each other i.e. with no replacement.
Dependent Events
Events that can not occur at the same time.
Mutually Exclusive Events
Events can occur at the same time.
Non-Mutually Exclusive Events
Frequently called the Gaussian distribution after ____________
Karl Freidrich Gauss
