Normal curve tests of means and proportions can also be called hypothesis testing. Normal curve tests of means and proportions are used to test the significant difference between two samples. Normal curve tests of means and proportions can also be used to test the significant difference of single mean from zero. Normal curve tests of means and proportions is a parametric test and normal curve tests of means and proportions becomes more powerful than two sample non parametric tests when its assumptions are satisfied.
There are certain terminologies in normal curve tests of means and proportions which will help in understanding normal curve tests of means and proportions in a much better manner:
Deviation scores in normal curve tests of means and proportions are the difference of the observed scores from its mean.
Standard deviation in normal curve tests of means and proportions is the measure of variation in the data.
Variance in normal curve tests of means and proportions is the variability in the data. In other words, variance is the amount by which the data varies.
Confidence limits in normal curve tests of means and proportions is the upper and lower limit which specify some range by which the estimates vary.
A binomial distribution in normal curve tests of means and proportions is a discrete probability distribution, which is based on dichotomous variables like two sides of a coin etc.
A normal distribution in normal curve tests of means and proportions is based on continuous and large sample data. Normal distribution takes the form of a symmetric bell-shaped curve.
Assumptions
In normal curve tests of means and proportions, the variables to be estimated are generally assumed from normal distribution.
Data in normal curve tests of means and proportions is assumed to be interval in nature. Interval data is based on an interval scale in which the numbers are used to rate the objects.
A large sample size in normal curve tests of means and proportions should be assumed.
The variances should be homogeneous in nature in normal curve tests of means and proportions.
