What are 4 different measurement scales?
What is nominal data?
Data is a name.
What is ordinal data
Data is a rating.
e.g. pain level
What is interval data?
Data is a number with regular intervals between but has no true zero.
What is ratio data?
Data has a zero level, intervals with units.
e.g. weight, height
What is inferential statistics?
To select a sample and use statistics to make generalizations about a population
What is a parameter?
A numerical characterisitic of a population
What are two types of inferential statistics procedures?
- Estimation of parameters
- Hypothesis testing
What can an estimation of parameters be?
It can be a single number or an interval
A single value is....
A point estimate.
e.g mean age
What is an interval estimate?
It is a range of values.
e.g. ages 16-20
What is confidence interval associated with?
It is associated with the interval estimate chosen.
hat is the procedure in hypothesis testing?
- Formulate a hypothesis about the characterisitc to be studied.
- Sample a population
- Make an objective decision about the results of the study
What must be taken into account in hypothesis testing?
Must take the probability into account to be sure that the results are not just due to chance.
What does probability do in hypothesis testing?
It helps check the accuracy of a statistic and test the hypothesis.
What are two types of hypothesis testing?
- Parametric procedures
- Nonparametric procedures
What is probability?
It is the likelihood that an event will occur given all the possible outcomes.
What type of system is probability?
It is a system of rules for analyzing outcomes./
What does the confidence level establish?
It establishes the probability level that this is real.
What is the probability that the null hypothesis can be rejected and the research hopthesis can be accepted?
Researchers typically accept a confudence level of what?
.05 as good
What does the confidence level indicate?
It indicates what percentages of the values will be outside the standard deviations from the mean difference of 0
What does a .05 confidence level mean?
It means that chance may occur 5/100 and this is ok
How can confidence levels be set up?
They can be set up for any level of probability to show statistical significance.
A higher magnitude of probabiliity (p) does not indicate what?
It does not indicate that the hypothesis has more or less significance than another.
It is either significant or not significant, not more or less.
What are paramedic procedures?
Data is interval or ratio scale with specific distributions and groups must be mutually exclusive.
What is nonparametric procedures?
Data is ordinal or nominal scale with no assumptions about distribution.
More simple and less powerful.
What is a correlation?
It is the relationship between two variables.
What is correlation coefficient?
It is a decimal between +1.0 and -1.0
What does a (+) decimal indicate?
It indicates a positive correlation.
Same direction, direct relationship.
What does a (-) decimal indicate?
It indicates a negative correlation.
Different directions, indirect relationship.
The closer the correlation coefficient (r) is to (+)1.0 to (-)1.0 the ______ the correlation.
The closer the correlation is to 0, the _________ the correlation between the variables.
What does a t-test do?
It checks for differences between groups.
What type of statistic is a t-test?
What does t-test determine?
It determines whether there is a significant difference between the means of two groups.
What are some non-parametric statistic test?
- Variables have non-normal distributions
- Nominal or oridnal data
- Low sample size
What is the most commonly reported non-parametric statistic?
What is chi-square analysis?
The frequency of observed occurences compared to the expected frequencies based on theory or past experience.
Chi-square is a ______, not a ______.
What does central tendency consist of?
What does dispersion consist of?
- Standard deviation
What does distribution consist of?
- Normal distribution
- Symmetrical distribution
- Bell curve
- Skewed distribution
- Unimodal distribution
- Bimodal distribution
- Multimodal distribution
What type of statistics icnludes central tendency, dispersion and distribution?
What does parametric procedures consist of?
- Point estimate
- Interval estimate
- confidence interval
- Correlation coefficient
- Confidence level
What does non-parametric procedures consist of?
Parametric procedures is for what kind of data?
Interval ratio data
Non-parametric procedures is for what kind of data?
Nominal or ordinal data.
What type of statisics consist of non-parametric and parametric procedures?