Standardized measures seem to indicate that the average level of anxiety has increased gradually over the past 50 years. In the 1950's the average score on the Child Manifest Anxiety Scale was µ = 15.1. A sample of n = 16 of today’s children produces a mean score of M= 23.3 with SS = 240.(a)Based on the sample, has there been a significant change in the average level of anxiety since the 1950s? Use a two-tailed test with α = 0.01. State the null and research hypothesis  Sketch the sampling distribution and shade the part of distribution you're interested in Show calculations of the standard error and t score

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Confidence Intervals

When we calculate intervals in probability and statistics, it can be simply termed as finding out a confidence interval. The confidence interval is usually calculated from the data set which is observed. The value of the parameter that needs to be calculated is present here only.