Stats Test 3 Review

Front

What does a positive r value indicate in a line of best fit?

Back

A positive r value indicates a positive correlation between the variables, meaning as one variable increases, the other variable also tends to increase.

Front

What is the mean IQ score in a normally distributed population?

Back

The mean IQ score is typically set at 100.

Front

What is the standard deviation of IQ scores?

Back

The standard deviation of IQ scores is typically 15.

Front

What percentage of individuals have an IQ lower than 115 in a normal distribution?

Back

84% of individuals have an IQ lower than 115.

Front

What percentage of scores falls within one standard deviation of the mean in a normal distribution?

Back

Approximately 68% of scores fall within one standard deviation of the mean.

Front

What is the index number formula for calculating price changes?

Back

Index Number = (Current Price / Base Price) x 100.

Front

How do you calculate the index number for gasoline prices if 2019 = 100?

Back

Index Number for April 2022 = ($4.21 / $2.88) x 100 = 146.

Front

What is the effect on correlation when changing the units of measurement?

Back

Changing the units of measurement has no effect on the correlation.

Front

What does a standard deviation measure in a data set?

Back

Standard deviation measures the amount of variation or dispersion in a set of values.

Front

What is the empirical rule in statistics?

Back

The empirical rule states that for a normal distribution, approximately 68% of data falls within one standard deviation, 95% within two, and 99.7% within three standard deviations from the mean.