Exam 3 pt 2 Flashcards
when critical values fall in the tails of normal distributions
usually 2 standard deviations from the mean
statistically significant
when findings did not happen by chance alone
statistically significant
adjusting to the risk of making type 1 and type 2 errors
level of significance
when the results of the study could have occurred by chance
non significance
findings that support the null hypothesis
non significance
the probability of making a type 1 error
alpha level
typically designated as 0.05 or 0.01 at the end of the tail in a distribution
alpha level
what are the implications of alpha level 0.05
when alpha is 0.05, it is likely that 5 out of 100 times the researcher will make a type 1 error and wrongly reject the null hypothesis
what are the implications of alpha level 0.01
when alpha is 0.01, researcher will make type 1 error only 1 time out of 100
which type of alpha is more common
0.05
collection an presentation of data that explain characteristics of variables found in the sample
summarize, describe and synthesize collected data
descriptive statistics
analysis of data as the basis for prediction related to the phenomenon of interest
inferential statistics
used to make inferences and draw conclusions about a population based on a sample
develop population parameters
inferential statistics
inferential statistical tests involving interval or ration level data to make inferences about the population
parametric statistics
what are the specific conditions that must be met to be parametric statistics
1) use of probability sampling
2) normal distribution of data
3) measurement of variables at interval and ratio level
4) reduction of error
how confident are nurses about parametric statistic conclusions
high confidence
inferential statistics involving nominal or ordinal level data to make inferences about the population
non parametric statistics
less powerful test used when all four conditions are NOT met
low confidence about conclusion
non parametric statistics
low to high levels of measurement
nominal, ordinal, interval, ratio
lowest level of measurement
data are categorized simply into groups
categorical data
nominal
continuum of numeric values where intervals are not meant to be equal
ordinal
continuum of numeric values with equal intervals that lacks an absolute zero
interval
highest level of measurement
numeric values that begin with an absolute zero and have equal intervals
ratio
extension of research findings and conclusions from a study conducted on a sample population to the general population
generalizability
improve studies because precision of sample selection is enhanced
sampling criteria
characteristics that each element must possess to be included in the sample
clearly identify subjects of the study (ie/ age, ability to speak English)
Inclusion criteria
characteristics of elements that will NOT be included in the sample
may decreased the risks of certain characteristics influencing results
exclusion criteria
non probability sampling method in which elements are selected because they are easy to access
convenience sampling
random sampling method of selecting elements from larger to smaller subsets of an accessible population
multi staging sampling
cluster sampling
randomly selecting elements from the accessible population
simple random sampling
most effective method to obtain representation sample
simple random sampling
nonprobability sampling method used in quantitative studies
used to select a distinct group of individuals who either have lived the experience or have expertise about the experience being studies
purposive sampling
sampling method to recruit persons who could provide inside info
purposive sampling
nonprobability sampling method involving selection of elements from an accessible population that has been divided into groups or strata
quota sampling
sampling method in which elements in the accessible population have an equal chance of being selected for inclusion in the study
probability sampling
3 conditions to meet for probability sampling
identifiable accessible population
sampling frame
use of randomization
list of all possible elements in the accessible population
sampling frame
recruitment of participants based on word of mouth or referrals from other participants
network sampling
network sampling is also known as
snowball sampling
describe sample sizes of qual an quant
qualitative studies have smaller sample sizes
used to gather data about subjects at more than 1 point in time
longitudinal study
what are the threats of longitudinal study
mortality, maturation, testing
a statistical method to determine the acceptable sample size that will best detect the true effect of the independent variable
power analysis
powerful, accurate method to determine sample size for quantitative studies
power analysis
why are power analysis done
they ensure greater assurance that the sample size was appropriate for study
nurses can be confident applying findings to target population
what are the two factors of power analysis
significance level and effect size
alpha level established BEFORE beginning of study (common is 0.05=p)
significance level
estimate of how large a difference will be observed between the groups
effect size
