QQ conceptual

Leptokurtic means the SD is _____ of the range
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dependent variableeffectInferential statistics are referred to as 'inferential' because they are used to draw conclusions about ___ from ___.populations from sample dataOnly if the researcher manipulates an independent variable can a study be considered an experiment.trueWhat is a standard deviationThe average variation from the mean in a set of measurements in a sampleThe null hypothesis for the single-sample t-test is that any difference between the sample mean and the population mean is due tochance, random variation and sampling errorThe t-test or the z-test can be used if the dependent variable is nominal.False, both z and t rely on means and SDs, which are not relevant to nominal data, only to interval/ratio level data.When doing a t-test, our obtained t-value must ________ the critical value in the table (for the designated degrees of freedom) in order to _________ the null hypothesis.be equal to or greater than; rejecRejecting the null hypothesis means thatwe determined that the null hypothesis is unlikely to be trueWhen you know the population mean, but the population standard deviation is unknown, and you want to determine if a sample mean is "significantly different" from the population mean, you should use a(n)Single sample t testWhich of the following is FALSE with respect to the standard deviation?it can never be zeroWhen can the Standard deviation be zero?if all scores are identicalCharacteristics of normal distributionIts mean, median, and mode are all equal Its form is mesokurtic (the SD = 1/6 of the range) The areas under the curve are fixed (e.g., 68.26% of the area lies between +1 and -1 SD of the mean)With respect to the "sampling distribution of the mean,"the mean, median, and mode must all be equal to the population mean the distribution of the means must be normal, even if the actual population distribution from which the samples are taken is notWith respect to z-scores, for any sample the mean is always ___ and the SD is always __0 and sd is always 1In the t-statistic, the denominator represents variability in the DV due to ____________, while the numerator represents variability in the DV due to _______.everything except the independent variable; the independent variable and sampling error.If we use an alpha of .01 when testing the null hypothesis, what is the probability of making a Type II error?99%type one error meanswe rejected the null but we shouldn'tThe standard deviation can never be greater than ____1/2 the rangelarger sample size means smaller ______standard error of meanA frequency distribution would be mesokurtic if its standard deviation was 8 and its range was A. 16 B. 48 C. 96B. 48A negative z-score means that the value isbetween the 0 and 50th percentileAs σ gets larger, the standard error of the mean would _____ making it _____ likely to reject the null hypothesis.increase; lessIf a researcher wanted to determine if there was a difference between a sample of lawyers and a sample of doctors in their annual income (measured in dollars) the appropriate inferential statistic to use would be theindependent samples t-testIf we use an alpha of .05 when testing the null hypothesis, what is the probability of incorrectly rejecting the null hypothesis?5% (Using an alpha of .05 means the probability of making a Type I error is also 5%)Inferential statistics (such as the independent samples t and chi-square) are referred to as 'inferential' because they are used to draw conclusions about ___ from __populations; samplesWhen we fail to reject H0, we are concluding that the results (e.g., the difference between means) are due to _____sampling errorWith respect to estimating a population mean, compared to a 99% confidence interval, a 95% confidence interval will benarrowerWith respect to the level of measurement, for a chi-square test, the dependent variable is _____ and the independent variable is ______.nominal; nominalIn an independent samples t-test, the value of t tells you what?How many estimated standard errors of the difference you are above or below 0The computed value of t in an independent samples t test tells you how many ______ you are from _______estimated standard errors of the difference; 0If, in reality, there really is a difference between the unknown population mean (that a sample represents) and the population mean to which you are comparing it, the probability of making a Type I error iszeroWhen you beat the critical value and rejecting the null that means the DV had _____ effectno effectThe range is themeasure of variability (difference between highest and lowest values in the dataParameternumerical summary of a populationstatistica number that describes a sampleVariancea difference between what is expected and what actually occurs and the total of the squared difference between every score and the meanz testa frequency distribution of an infinite number of sample means of size N taken at random (sampling with replacement) from a population