Question

A researcher is testing a hypothesis of a single mean. The critical z value for a = .05 and a two‑tailed test is +1.96. The observed z value from sample data is ‑2.05. The decision made by the researcher based on this information is to _____ the null hypothesis.

Answer 1

Answer:

The decision made by the researcher based on this information is to reject the null hypothesis.

Step-by-step explanation:

Two-tailed hypothesis test:

Critical value: $z_c$

Test statistic: z

If $|z| < |z_c|$, we do not reject the null hypothesis.

If $|z| > |z_c|$, we reject the null hypothesis.

In this question:

$z_c = 1.96, z = -2.05, |z| = 2.05$

Since $|z| > |z_c|$, we reject the null hypothesis.

The decision made by the researcher based on this information is to reject the null hypothesis.