In a test with a z-score of 1.72, what type of hypothesis test was conducted?

A z-score of 1.72 generally indicates that the test is assessing the position of a sample mean or a sample proportion in relation to the population mean or proportion, based on standard deviation units. In hypothesis testing, the nature of your test—whether it is one-tailed or two-tailed—depends on the directionality of the alternative hypothesis.

In a one-tailed hypothesis test, the alternative hypothesis specifies a direction, either that the parameter is greater than or less than a certain value, which is what the z-score reflects. A z-score of 1.72 suggests that the test statistic falls within the region where you might reject the null hypothesis in favor of an alternative hypothesis that indicates an increase from a baseline (if the test is right-tailed) or a decrease (if the test is left-tailed).

Conversely, in a two-tailed test, the alternative hypothesis does not specify a direction (it merely suggests that a parameter is different—either greater or less than a certain value), leading to smaller critical regions at either end of the distribution. A z-score used in this type of test would typically be assessed against both a positive and negative critical value.

In the absence of additional context about the specific hypothesis being tested,