Question: Are Jack Bender and Roger Christian both film directors ?

full_context: Document 1: Alien (film): Alien is a 1979 science-fiction horror film directed by Ridley Scott, and starring Sigourney Weaver, Tom Skerritt, Veronica Cartwright, Harry Dean Stanton, John Hurt, Ian Holm and Yaphet Kotto. The film's title refers to a highly aggressive extraterrestrial creature that stalks and attacks the crew of a spaceship. Dan O'Bannon, drawing upon previous works of science fiction and horror, wrote the screenplay from a story he co-authored with Ronald Shusett. The film was produced by Gordon Carroll, David Giler and Walter Hill through their company Brandywine Productions, and was distributed by 20th Century Fox. Giler and Hill revised and made additions to the script. Shusett was executive producer. The eponymous Alien and its accompanying elements were designed by the Swiss artist H. R. Giger, while concept artists Ron Cobb and Chris Foss designed the more human aspects of the film.
Document 2: Battlefield Earth (film): Battlefield Earth (also referred to as Battlefield Earth: A Saga of the Year 3000) is a 2000 American science fiction action film based upon the first half of L. Ron Hubbard's 1982 novel of the same name. Directed by Roger Christian and starring John Travolta, Barry Pepper and Forest Whitaker, the film depicts an Earth that has been under the rule of the alien Psychlos for 1,000 years and tells the story of the rebellion that develops when the Psychlos attempt to use the surviving humans as gold miners.
Document 3: David Chase: David Chase (born August 22, 1945) is an American writer, director and television producer. Chase has worked in television for 40 years; he has produced and written for such shows as "The Rockford Files", "I'll Fly Away", and "Northern Exposure". He has created two original series; the first, "Almost Grown", aired for 10 episodes in 1988 and 1989. Chase is best known for his second original series, the influential and critically acclaimed HBO drama "The Sopranos", which aired for six seasons between 1999 and 2007. He is a prominent figure in American television and has won seven Emmy Awards.
Document 4: Lawrence Bender: Lawrence Bender (born October 17, 1957) is an American film producer. He rose to fame by producing "Reservoir Dogs" in 1992 and has since produced all of Quentin Tarantino's films with the exception of "Death Proof", "Django Unchained" and "The Hateful Eight". He also produces documentary films, most notably the controversial film "An Inconvenient Truth" (2006).
Document 5: Chris Corbould: Christopher Charles Corbould, {'1': ", '2': ", '3': ", '4': "} (born 1958) is a British special effects coordinator best known for his work on major blockbuster films and the action scenes on some 11 "James Bond" films since the early 1980s. He has also worked extensively on the "Superman" and "Batman" film series on digital effects and stunts. Corbould has been awarded two Honorary Doctorates from Southampton Solent University in December 2009 and University of Hertfordshire in 2011. In 2011, he won the Academy Award for Best Visual Effects at the 83rd Academy Awards for his work on "Inception". He is the brother of special effects supervisors Neil Corbould and Paul Corbould.
Document 6: Black Angel (1980 film): Black Angel is a 1980 British short film that was shown before the theatrical release of "The Empire Strikes Back" in certain locales. It was the directorial debut of "Star Wars" art director Roger Christian. The film negative was thought to be lost until it was rediscovered in December 2011. In June 2015, it was announced that Christian was working on a feature film adaptation of "Black Angel", which would be in part funded on crowd-funding site, Indiegogo.
Document 7: Ridley Scott: Sir Ridley Scott (born 30 November 1937) is an English film director and producer. Following his commercial breakthrough with the science-fiction horror film "Alien" (1979), his best known works include the neo-noir dystopian science fiction film "Blade Runner" (1982), historical drama and Best Picture Oscar winner "Gladiator" (2000), and science fiction film "The Martian" (2015).
Document 8: Roger Christian (filmmaker): Roger Christian (born 25 February 1944) is an English set decorator, production designer and feature film director. He won an Academy Award for his work on the original "Star Wars" and was Oscar-nominated for his work on "Alien". Christian directed the second unit on both "Return of the Jedi" and "" as well as feature films including "The Sender" and "Nostradamus". He also directed the 2000 film "Battlefield Earth" which is regarded as one of the worst films ever made.
Document 9: Game of Thrones: Game of Thrones is an American fantasy drama television series created by David Benioff and D. B. Weiss. It is an adaptation of "A Song of Ice and Fire", George R. R. Martin's series of fantasy novels, the first of which is "A Game of Thrones". It is filmed in Belfast and elsewhere in the United Kingdom, Canada, Croatia, Iceland, Malta, Morocco, Spain, and the United States. The series premiered on HBO in the United States on April 17, 2011, and its seventh season ended on August 27, 2017. The series will conclude with its eighth season in 2018 or 2019.
Document 10: Jack Bender: Jack Bender (born September 25, 1949) is an American television and film director, television producer and former actor best known for his work as a director on "Lost", "The Sopranos" and "Game of Thrones".
Document 11: James Gandolfini: James Joseph Gandolfini Jr. (September 18, 1961 – June 19, 2013) was an American actor and producer. He was best known for his role as Tony Soprano, an Italian-American crime boss, in the HBO crime drama "The Sopranos". He garnered enormous praise for his performance, winning three Emmy Awards, three Screen Actors Guild Awards, and one Golden Globe Award.
Document 12: Nick Allder: Nick Allder is an English special effects supervisor and coordinator. He started his career as an assistant camera operator and moved, after eight years, into special effects. He has won multiple awards, including an Academy Award for Best Visual Effects for the science-fiction horror film "Alien" (1979), and a BAFTA Award for Best Special Visual Effects for the science-fiction film "The Fifth Element" (1997). Allder has worked on the set of high-grossing films such as the epic space opera "The Empire Strikes Back" (1980) and the historical drama film "Braveheart" (1995).
Document 13: Matthew Weiner: Matthew Weiner ( ; born June 29, 1965) is an American writer, director and producer. He is the creator of the AMC television drama series "Mad Men", which premiered in 2007 and ended in 2015. He is also noted for his work on the HBO drama series "The Sopranos", on which he served as a writer and producer during the show's fifth and sixth seasons (2004; 2006–2007). He directed the comedy film "Are You Here" in 2013, marking his filmmaking debut.
Document 14: Jack Shephard: Dr. Jack Shephard is a fictional character and the main protagonist of the ABC television series "Lost", played by Matthew Fox. "Lost" follows the journey of the survivors of Oceanic Airlines flight 815 on a mysterious island and their attempts to survive and escape, slowly uncovering more of the much broader island history they are a part of. The character was originally conceived by creator J. J. Abrams, though the direction of storylines owes more to co-creator Damon Lindelof and fellow showrunner Carlton Cuse. J.J. Abrams, the creator of "Lost", once told "Entertainment Weekly", "Jack Shephard may be the greatest leader in any television series." Actor Matthew Fox would have some influence on the character during the course of the series' production. For example, Fox's own tattoos were incorporated into the character's backstory. Although at an early stage in the show's development, the character was originally intended to die in the pilot, the writers soon changed this plan, and Jack became the show's main character from its pilot episode onwards.
Document 15: Jon Cassar: John Francis "Jon" Cassar (born April 27, 1958) is a Maltese-Canadian television director and producer, known for his work on the first seven seasons of "24". In 2006, he won the Primetime Emmy Award for Outstanding Directing for a Drama Series for his work on the episode "". In 2011, he produced and directed all episodes of the Canadian-American miniseries "The Kennedys", for which he won the Directors Guild of America Award for Outstanding Directing – Television Film and was nominated for the Primetime Emmy Award for Outstanding Miniseries or Movie.
ground_truth: yes