Chapter 3 Terms Flashcards
Computer-calculated plot or graph estimating the relationship between two variables.
Trend Line
The text’s name for a one-tail test.
One sided Alternative
The text’s name for a two-tailed test
Two sided Alternative
Sometimes called “matched pairs” where two sets of data provide similar observations under similar conditions
Paired Data
Common Excel test to assess similarity in the means between two similar sample groups for which population mean is unknown.
t- test, paired two sample for means
Common Excel test to assess similarity in the means between two sets of data when the variance and standard deviations are unknown, but where the researcher believes that characteristics of the groups may be similar.
t-test, assuming equal variance
Common Excel test to assess similarity in the means between two sets of data when the variance and standard deviations are unknown, and where the researcher believes that characteristics of the groups are not similar.
t-test, assuming unequal variance
comparison of two columns of data testing for similarity in means and where there are different numbers of observed values.
Z-Test, 2 Sample for Means: Excel
Two columns of data providing results from two separate and independent groups
Independent data
Comparison of Expected Values with observed values to test how closely they match.
Goodness of Fit
The sum of the squared differences between the observed values and the expected values used to assess how similar they are. Numerically high X2 values indicate poor fit between observed and expected values.
Chi Squared (X2) Statistic
Term used for the differences (positive & negative) between observed values and expected values.
Residuals
Comparison of two variables to see if values for one consistently affect values for the other
Test for Independence
The variable presumed to cause change in the dependent variable
Independent Variable
The variable presumed to be changed as a result of changes in the independent variable.
Dependent Variable
(Sometimes called a scatter diagram.) A graphical illustration of the intersection of values of the independent variable x, and values of the dependent variable y.
Scatter plot
Conversion of values for 2 variables in separate columns to a scatter plot diagram which can also produce a regression trendline, regression formula and R2 display
Excel Scatter plot
Calculation of the relationship between two variables that produces a formula (y-hat= b0 + b1 x) calculating a straight line approximating the probable values resulting from a data set of x and y variables.
Simple Linear Regression
Calculation of the relationship between more than one independent variable (x value) and the dependent variable (y value).
Multiple Linear Regression
Portion of the distribution chosen to determine acceptable test results (e.g.95%)
Confidence level
Conversion of confidence level to a decimal value (e.g. 95% to 0.9500
Confidence Coefficient
A calculation performed by Excel measuring strength of the relationship (reliability) between the trendline created by the regression formula and the observed intersecting values of the x and y variables.
R Squared or R2 Calculation (aka Coefficient of Determination)
A calculation performed by Excel measuring the strength of the relationship between the values of the x and y variables. It is the square root of the R2 value.
Multiple R (aka Correlation Coefficient)
A value in a data set that is significantly higher or lower than 95% of the distribution which requires separate analysis and interpretation.
Outlier