AHIC Review Course 2: Descriptive and Inferential Statistics

Flashcards covering descriptive and inferential statistics concepts: definitions, measures, tests, assumptions, and common usage in healthcare analytics.

What is descriptive statistics?

The description of characteristics and features of a sample or population through specific measures (e.g., measures of central tendency and variability).

What are the two major categories in statistics?

Descriptive statistics and inferential statistics.

What are the two main categories of descriptive statistics measures?

Measures of central tendency and measures of variability.

Name the common measures of central tendency.

Mode, median, and mean.

When is mode an appropriate measure of central tendency?

Mode is appropriate for nominal data.

What is the median?

The value that divides the data into a higher half and a lower half.

What is the mean?

The average, calculated by adding all values and dividing by the number of data points.

When might the median be preferred over the mean?

When there are outliers in the data set, the median can be a better representative of the central point.

What are the measures of variability?

Range, variance, and standard deviation.

What does the range measure?

Difference between the highest and the lowest value in the data set.

What does the variance measure?

How far data points are from the mean, using the squared deviations.

What does the standard deviation represent?

The square root of the variance; it measures dispersion around the mean.

What are descriptive statistics graphs used for?

To describe data visually, using graphs like bar graphs and pie charts to illustrate characteristics and proportions.

What is inferential statistics?

Statistics that infer properties of a population from a sample and generalize findings.

What are the two main categories of inferential statistics tests?

Parametric and nonparametric tests.

What characterizes nonparametric tests?

Distribution-free; do not assume a specific distribution; used when data are nominal/ordinal and not normally distributed.

What characterizes parametric tests?

Assume data are drawn from a population that follows a normal distribution and meet other assumptions.

Name three common parametric tests.

T-test, ANOVA, and linear regression.

What is the independent samples t-test used for?

To compare the means of two groups; the null hypothesis is that there is no significant difference between the two means.

What are the assumptions of the independent samples t-test?

Data are continuous or ordinal; data come from a representative random sample; data are approximately normally distributed; reasonably large sample size; and homogeneity of variance.

What is ANOVA used for and what are its limitations?

ANOVA compares the means of two or more independent groups (one-way or two-way); it can show if at least two groups differ but cannot identify which groups differ without further post hoc tests; requires homogeneity of variance and approximate normality of the dependent variable.

What is regression analysis?

A set of statistical processes to determine the relation between one or more independent variables and a dependent variable; simple linear regression uses one independent variable and multiple linear regression uses two or more.

Which software platforms are commonly used to perform these inferential tests?

SPSS, Minitab, SAS, or R.

What is the knowledge-check answer regarding comparing average hospitalization costs between two groups?

T-test (independent samples t-test) is the appropriate test.

What is the null hypothesis for the t-test in comparing two group means?

There is no significant difference between the two means.