A researcher is investigating whether a reading intervention program improves reading comprehension for second graders. He collects a random sample of second graders and randomly assigns each second grader to participate in the reading intervention program or not participate in the program. The researcher knows that the standard deviation of the reading comprehension scores among all second graders is σ = 25.24.
Group 1 consists of n₁ = 52 second graders who did not participate in the program. Their mean reading comprehension score is M₁ = 36.8. Group 2 consists of n₂ = 56 second graders who did participate in the program. Their mean reading comprehension score is M₂ = 52.4.
Of the plots that follow, which best represents a plot of these results?

The brackets or error bars shown at the top of each bar extend _ above and below each of the group means. For group 1, the error bar extends _units above and below the mean for group 1.

The brackets or error bars shown at the top of each bar extend one standard error above and below each of the group means. For group 1, the error bar extends 3.9 units above and below the mean for group 1.

A researcher is investigating whether a reading intervention program improves reading comprehension for second graders. He collects a random sample of second graders
Group 1 consists of n₁ = 52 second graders who did not participate in the program. Their mean reading comprehension score is M₁ = 36.8.
Group 2 consists of n₂ = 56 second graders who did participate in the program. Their mean reading comprehension score is M₂ = 52.4.

What is Error bars?

Error bar, are the line through a point on a graph,axes, which emphasizes the uncertainty or variation of the corresponding coordinate of the point.

We have the data,
σ = 25.24, n₁ = 52 M₁ = 36.8.

n₂ = 56 M₂ = 52.4.

Error bar = M2-M1/n2-n1
= (52.4-36.8)/(56-52)
= 3.9

Thus, the required value that will be put in black space is 3.9

Learn more about error bar here:
https://brainly.com/question/14639901

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