Trevor thinks that left-handed pitchers in a baseball league are more likely to strike out batters than right-handed pitchers are. He's considering each "at-bat" as an opportunity for a strikeout. He takes a random sample of at-bats where the pitcher was left-handed, and he records the proportion of those at-bats that result in a strikeout. He repeats this process for at-bats with right-handed pitchers. He wants to use the results to test if the proportion of at-bats resulting in a strikeout is significantly higher for left-handed pitchers. Which of the following is an appropriate set of hypotheses for Trevor'?
A. H0: PR - PL = 0
Ha: PR - PL > 0
B. H0: PL - PR = 0
Ha: PL - PR < 0
C. H0: PM - PR = 0
Ha: PL - PR > 0
D. H0: PR - PL = 0
Ha: PR - PL not equal to 0

Respuesta :

Answer:

C. H0: PL - PR = 0

Ha: PL - PR > 0

The null hypothesis for this case is that left-handed pitchers in a baseball league are not more likely to strike out batters than right-handed pitchers are. That is the proportion of at-bats resulting in a strikeout is significantly equal for both left-handed and right-handed pitchers.

H0: PL - PR = 0

The alternative hypothesis is that the proportion of at-bats resulting in a strikeout is significantly higher for left-handed pitchers

Ha: PL - PR > 0

PL - proportion of at-bats resulting in a strikeout for left-handed pitchers

PR - proportion of at-bats resulting in a strikeout for right-handed pitchers

Step-by-step explanation:

The null hypothesis (H0) tries to show that no significant variation exists between variables or that a single variable is no different than its mean. While an alternative Hypothesis (Ha) attempt to prove that a new theory is true rather than the old one. That a variable is significantly different from the mean.

The null hypothesis for this case is that left-handed pitchers in a baseball league are not more likely to strike out batters than right-handed pitchers are. That is the proportion of at-bats resulting in a strikeout is significantly equal for both left-handed and right-handed pitchers.

H0: PL - PR = 0

The alternative hypothesis is that the proportion of at-bats resulting in a strikeout is significantly higher for left-handed pitchers

Ha: PL - PR > 0

PL - proportion of at-bats resulting in a strikeout for left-handed pitchers

PR - proportion of at-bats resulting in a strikeout for right-handed pitchers