Definitions: Chapter 8 Flashcards
Sample Statistics:
the mean or a deviation of a computed sample
Sampling Error:
variability of a statistic from sample to sample due to chance
Hypothesis testing:
process by which decisions are made concerning the value of parameters
Sampling distribution:
the variability of a statistic over a repeated sampling from a specified population
-a repeated STATISTIC (not raw score)
Standard error
the standard deviation of the sampling distribution
sampling distribution of the mean:
the distribution of same means over repeated sampling from one population
Research hypothesis:
a hypothesis that the experiement was designed to investigate:
example: Does CBT have any affect on an anorexic girls weight?
Null Hypotheses
statistic hypotheses tested by a procedure- saying that there is no relationship
example: CBT has no affect on anorexic girls weight.
Alternate Hypotheses
statistic hypotheses in which we are looking to find- what we will recieve if the NULL is untrue
Example: yes, CBT does have a n effect on anorexic girls weight
Sample statistic:
stats calculated from a sample and used primarily to describe a sample
Test statistic:
the result of a stats test? wtf
Decision making:
procedure for making logical decisions basis of sample data
rejection level (signficance level)
the probability of which we are willing to reject when it in fact correct 5%
Rejection region:
the set of outcomes of an experiment that will lead to rejection of null
Critical value:
the value of a test statistic at or beyond which we will reject the null
type 1 error
Error of rejecting the null when its true (false positive)
what does alpha and beta represent
alpha: probability of a type 1 error
beta: probability of a type 2 error
type 2 error
error of not rejecting the null when its false
false negative
power:
probability of correctly rejecting a false null hypotheses
Differentiate between one tailed and two tailed test
One tailed is directional- meaning that the direction is at a specific tail of the distribution and you only reject on one side (negative/positive less/more)
two tailed is non directional: rejects extreme values and outcomes at each tail of the distribution
