AP Stats 1B

Exploring Data

100

This measure of center is more resistant to outliers than the mean.

Median

200

To calculate, subtract the mean of the distribution from the observed x, then divide by the standard deviation.

z-score or standardized score

300

This rule helps to determine if data is normally distributed by checking the number of observations within each interval.

68-95-99.7 Rule

400

This calculator command can be used to find the area under a normal distribution and above an interval.

normalcdf

500

This calculator command can be used to find a value in a normal distribution for which a certain percentage of the data is above or below.

invnorm

Bivariate Data

100

observed y - predicted y

Residual

200

Measures the strength and direction of a linear relationship between two quantitative variables.

Correlation Coefficient

300

The percentage of the variability in y that is explained by x.

Coefficient of Determination

400

A wildlife biologist is interested in the relationship between the number of chirps per minute for crickets (y) and temperature. Based on the collected data, the least squares regression line is, y = 10.53 + 3.41x, where x is the number of degrees Fahrenheit by which the temperature exceeds 50. Interpret the slope of the LSRL.

As temperature increases by 1 degree Fahrenheit over 50 degrees, the number of chirps per minute for crickets increases by 3.41.

500

A wildlife biologist is interested in the relationship between the number of chirps per minute for crickets (y) and temperature. Based on the collected data, the least squares regression line is, y = 10.53 + 3.41x where x is the number of degrees Fahrenheit by which the temperature exceeds 50. R-sq = 0.86. Interpret the coefficient of determination.

86% of the variability in the number of chirps per minute for crickets can be explained by the linear model.

Experiments

100

Identify three ways to generate random numbers.

Names in a hat, random number generator, random number table.

200

Identify the term that describes your brain convincing your body that a real treatment was received.

Placebo Effect

300

This experimental design involves the random assignment of units to treatments which are carried out separately within each group of units known to be similar in some way that is expected to affect the responses.

Block Design

400

The 3 basic principles of experimental design.

Randomization, Control and Replication

500

Identify this type of experiment: Two ski gloves. Apply water repelling wax to the left glove and water repelling spray to the right glove. Compare how long the gloves repel water.

Matched Pairs