Test of Equality of Variances When testing two independent samples (for differences in mean, one-sided tests, etc.), it is helpful to know that the samples have equal variances or not.
JHK2303/iStock/Getty Images. Chambray, a double-ply cotton fabric with a tight weave, is similar to denim but not the same. It has a white filler thread woven in with a colored background thread. But unlike denim's twill weave, chambray has a plain weave, so it's smoother and lighter in weight.Chambray is rugged but light, making it suitable for work wear as well as summer-weight shirts and skirts.ut unlike denim's twill weave, chambray has a plain weave, so it's smoother and lighter in weight. Chambray is rugged but light, making it suitable for work wear as well as summer-weight shirts and skirts.
DMC Pearl Cotton is a highly mercerized, non-divisible, lustrous 100% cotton thread on a twisted skein. The twist of the thread is how it received its âPearlâ description and DMCâs Pearl Cotton is best known as the most beautiful thread in the world. During the manufacturing process, the thread is combed, singed by flame and then double mercerized.